1. Absolute Linux
Absolute Linux is a light-weight modification of Slackware Linux. It includes several utilities that make configuration and maintenance easier and it has many common desktop and Internet applications installed and configured with tight integration of menus, applications and MIME types. Absolute Linux uses IceWM and ROX for its window and file managers.
2. antiX
antiX is a fast, lightweight and easy-to-install linux live CD distribution based on MEPIS and Debian's testing branch for Intel/AMD x86-compatible systems. antiX offers users the "Magic of MEPIS" in an environment suitable for old computers. The goal of antiX is to provide a light, but fully functional and flexible free operating system for both newcomers and experienced users of Linux. It should run on most computers, ranging from 64 MB PII systems with a pre-configured 128 MB swap partition to the latest powerful boxes. 128 MB RAM is the recommended minimum for antiX while the installer needs a minimum of 2.2 GB hard disk space. antiX can also be used as a fast-booting rescue CD.
3. ConnochaetOS
ConnochaetOS (formerly DeLi Linux) is an Arch-based Linux distribution for old computers, from i486 to Pentium MMX 166. It's focused on desktop usage. It includes email clients, a graphical web browser, an office package with word processor and spreadsheet. A full install, including X window system and development tools, needs no more than 300 MB of hard disk space.
4. GALPon MiniNo
GALPon MiniNo is a lightweight, Debian-based distribution designed for PCs that are 10 years old (or more), though it's also perfectly usable on modern computers and netbooks. It contains a carefully tuned selection of applications that try to maintain a balance between features, ease of use and speed. IceWM with ROX-Filer and PCManFM provides the desktop. The distribution has full support for three languages (English, Galician and Spanish) and it also comes with "magic icons" - a set of tools that automate repetitive or system tasks (e.g. rotate or resize hundreds of digital images, convert audio or video files into other formats or burn an audio CD with a simple drag & drop).
5. Legacy OS
Legacy OS (formerly TEENpup Linux) is a distribution based on Puppy Linux. Although the original concept was to create a flavour of Puppy Linux with more applications and a more appealing desktop aimed at teenage users, Legacy OS has now grown to become a general purpose distribution. It comes with a large number of applications, browser plugins and media codecs as standard software. Despite these enhancements Legacy OS is still perfectly suitable for installation on older and low-resource computers, as well as modern hardware.
6. LinuxConsole
LinuxConsole is an independently developed Linux live CD with different editions designed for desktops, servers, gaming consoles, and old computers. Its primary characteristics are easy installation, extensive choice of software in the form of modules, and excellent hardware detection.
7. Lubuntu
Lubuntu is a fast, lightweight and energy-saving variant of Ubuntu using the LXDE (Lightweight X11 Desktop Environment) desktop. It is intended to have low-resource system requirements and is designed primarily for netbooks, mobile devices and older PCs.
8. PapugLinux
PapugLinux is a minimal GNU/Linux live CD based on the Gentoo Linux distribution for x86 computers. The goal of PapugLinux is to provide a minimal but functional free operating system which can be run on most computers, from old systems with as little as 64 MB of memory to the latest powerful configurations.
9. Puppy Linux
Puppy Linux is yet another Linux distribution. What's different here is that Puppy is extraordinarily small, yet quite full-featured. Puppy boots into a ramdisk and, unlike live CD distributions that have to keep pulling stuff off the CD, it loads into RAM. This means that all applications start in the blink of an eye and respond to user input instantly. Puppy Linux has the ability to boot off a flash card or any USB memory device, CDROM, Zip disk or LS/120/240 Superdisk, floppy disks, internal hard drive. It can even use a multisession formatted CD-RW/DVD-RW to save everything back to the CD/DVD with no hard drive required at all.
10. Quirky
Quirky, a sister project of Puppy Linux, is a Linux distribution built with a custom tool called Woof. The underlying infrastructure, such as boot-up and shut-down scripts, setup tools, hardware detection, desktop management, user interface, speed and general ease-of-use are common across all distributions built with Woof, but a specific build will have a different package selection and further customisation (even totally different binary packages). Quirky is developed by the founder of Puppy Linux and Woof to push the envelope a bit further, to explore some new ideas in the underlying infrastructure -- some of which may be radical or odd, hence the name Quirky.
11. SliTaz GNU/Linux
SliTaz GNU/Linux is a mini distribution and live CD designed to run speedily on hardware with 256 MB of RAM. SliTaz uses BusyBox, a recent Linux kernel and GNU software. It boots with Syslinux and provides more than 200 Linux commands, the lighttpd web server, SQLite database, rescue tools, IRC client, SSH client and server powered by Dropbear, X window system, JWM (Joe's Window Manager), gFTP, Geany IDE, Mozilla Firefox, AlsaPlayer, GParted, a sound file editor and more. The SliTaz ISO image fits on a less than 30 MB media and takes just 80 MB of hard disk space.
12. Swift Linux
Swift Linux is a lightweight, antiX-based distribution featuring the IceWM window manager. Compared to its parent, Swift Linux includes extra applications, such as BleachBit (a tool for freeing up space and clearing private information), the OpenOffice.org office suite, and a wide variety of forensic analysis and data recovery utilities.
13. Tiny Core Linux
Tiny Core Linux is a 10 MB graphical Linux desktop. It is based on the Linux 2.6 kernel, BusyBox, Tiny X, Fltk, and Flwm. The core runs entirely in memory and boots very quickly. The user has complete control over which applications and/or additional hardware to have supported, be it for a desktop, a nettop, an appliance or server; selectable from the project's online repository.
14. TinyMe
TinyMe is a Unity Linux-based mini-distribution. It exists to ease installation of Unity Linux on older computers, to provide a minimal installation for developers, and to deliver a fast Linux installation for where only the bare essentials are needed.
15. Toutou Linux
Toutou Linux is a French variant of Puppy Linux, a minimalist, yet powerful and extremely fast Linux distribution for the desktop. It is especially suitable to Linux beginners. It features the JWM window manager, SeaMonkey as the default Internet browser and a variety of lightweight applications, including some custom configuration utilities. The project also provides extra software packages, converted into French, for free download.
16. Unity Linux
The community-oriented Unity Linux is a minimalist distribution and live CD based on Mandriva Linux. The project's main goal is to create a base operating system from which more complete, user-oriented distribution can easily be built - either by other distribution projects or by the users themselves. Unity Linux uses Openbox as the default window manager. Its package management is handled via Smart and RPM 5 which can download and install additional software packages from the project's online repository.
17. VectorLinux
Vector Linux is a small, fast, Intel based Linux operating system for PC style computers. The creators of Vector Linux had a single credo: keep it simple, keep it small and let the end user decide what their operating system is going to be. What has evolved from this concept is perhaps the best little Linux operating system available anywhere. For the casual computer user you have a lightening fast desktop with graphical programs to handle your daily activities from web surfing, sending and receiving email, chatting on ICQ or IRC to running an ftp server. The power user will be pleased because all the tools are there to compile their own programs, use the system as a server or perhaps the gateway for their home or office computer network. Administrators will be equally as pleased because the small size and memory requirements of the operating system can be deployed on older machines maybe long forgotten.
18. wattOS
wattOS is a fast desktop Linux distribution based on Ubuntu. Using the lightweight Openbox window manager as its default user interface, the distribution strives to be as energy-efficient as possible so that it can be used on low-specification and recycled computers.