Flash Optimizer
Flash Optimizer is a handy software solution for web-masters, web-designers, Flash professionals and everyone who has ever come in touch with Macromedia Flash technology. It manages to reduce your SWF files size up to 60-70% thanks to amazing algorithms of vectors, shapes, morphing, Z-buffer,... Unlike any other similar software Flash Optimizer manages to optimize not only a separate part of your Flash movie, but the whole SWF, including curves, zero-objects, ZLib optimization and a whole lot more advanced techniques.
http://www.flashoptimizer.com/_download/flash_optimizer.exe - 3Mb - Download - Screenshot

Internet Cyclone
Internet Cyclone is a powerful, easy-to-use, Internet Optimizer for Windows 95, 98, ME, NT, 2000 and XP designed to automatically optimize your Windows settings wich will boost your Internet connection up to 200%. Internet Cyclone is compatible with all modems and high-speed LAN, ISDN, CABLE,... This Internet Connection optimizer speeds up Web browsing, file downloading, e-mailing, online gaming, chat and all other Internet related software utilities by preventing the data fragmentation during transmission.
ftp://ftp.monash.edu.au/pub/winxp/netutil/cyclone.zip - 956Kb - Download - Screenshot

Super System Helper
The perfect complement to firewalls and anti-virus software. Complete control over all running processes,show all open ports and maps them to running processes,show all DLLs loaded or Windows opened by each process,terminate or block any process,manage start-up applications and Browser Helper... Protect your system from viruses,trojans and spyware.
http://www.qwerks.com/download/7790/SystemHelper.exe - 4Mb - Download - Screenshot

Turbo Memory
Optimize your cache to act as a ram booster and boost computer speed. Discover extreme pc speed with Internet software solutions. Windows fills up your computer's memory (RAM)and finally RAM is filled with unnecessary application and system data. Turbo Memory RAM Booster recovers your... Turbo Memory RAM Booster boosts the physical memory available to Windows 95/98/2000/NT/Me/XP. ... You don't need to reboot your computer anymore.
http://www.backup.tc/downloads/TurboMemory2.4TrialVersion.exe - 16Mb - Download - Screenshot

Registry Cleaner
Registry Cleaner is a one click tool to scan, identify and fix errors in the system registry (reference files for programs installed on the computer). Normal usage of the system and regularly adding and removing programs leave unwanted traces in the registry like marks on a white board. ... For registry optimize, Registry Cleaner comes with the Express and the Wizard mode. ... Due to the extensive research put in by the development team, Registry Cleaner will optimize the registry like no other program, and that too without any risk.
http://toppctools.swmirror.com/registrycleaner.exe - 2Mb - Download - Screenshot

Advanced Windows Optimizer
Advanced Windows Optimizer is an award winning collection of tools to optimize and speedup your system performance. it contains utilities to clean registry, temporary files on your disks, erase your application and internet browser history, cache, cookies and more. ... you can control startup programs that load automatically with windows, find duplicate files, fix broken shortcuts and uninstall software. ... the built-in scheduled task manager allows you to schedule the cleaning tasks that take place automatically, other features include secure file deletion, shred recycle bin, application...
http://www.gogsoft.com/downloads/awoinstall.exe - 3Mb - Download - Screenshot

Control TOTAL
Multifunctional tweak: optimizing and expansion of Windows XP functiona Is the unique set of TOTAL utilities. More than 100 additional possibilities Control TOTAL ? is widening of your Windows XP function possibilities.
http://www.controltotal.atvsoft.com/controltotal.exe - 781Kb - Download - Screenshot

HideHelper - Hide windows and tray icons
1. HideHelper supports powerful function of defining hotkeys(Hide/Show): one is temporary hotkeys,the other is permanent hotkeys,you can Hide/Show one or a group of windows by pressing the hotkeys being attached with specific conditions 2. HideHelper can change the icon and title of any window. ... HideHelper provides the password-protection function which can lock HideHelper to ensure security of those hidden windows 8. ... HideHelper is developed by standard Windows API and optimized by good arithmetic,so it only costs few system resource In addition: HideHelper also provides a...
http://www.qwerks.com/download/7848/HideHelper.exe - 701Kb - Download - Screenshot

OptimizeXP Internet/Network Edition
Optimize and tweak your Windows XP Internet and Network settings to increase your internet speeds and make your network more stable. OptimizeXP comes with over 20 tweaks and optimizations to ensure that your internet expierence is as good as it can be. ... Don't forget to check out the other 3 editions of OptimizeXP! ... OptimizeXP comes with free on-line support.
http://www.econceptsoftware.com/downloads/OXP_internet.exe - 703Kb - Download - Screenshot

Paraben's I-Jolt
Paraben's I-Jolt helps you optimize your Internet connection. By tweaking your Maximum Transmission Unit (MTU), Maximum Segment Size (MSS), Receive Window (RWIN), Time To Live (TTL), MTU Auto Discover, and Black Hole detection you can obtain faster throughput. ... The group settings include Optimal, Default, PPP, and more. ... Change these settings manually, one at a time, or select one of several buttons that change the settings as a group. ... If you don't know how to do this yourself, I-Jolt is the tool for you.
http://www.paraben.com/programs/ijolt.exe - 1Mb - Download - Screenshot