1)   MemMonster 4.65
MemMonster - Tune Up RAM performance in just 30 seconds. This software will monitor and increase your available RAM up to 300%, it works great with Windows XP,2000,Me,9x

 2)   Free Up Ram 1.15
Free Up Ram is a simple, yet robust memory optimizer. Free Up Ram was designed to allow you to quickly free up physical memory taken up or used by applications and processes no longer in use by your computer.

 3)   Power Memory Booster Free Version 5
Power Memory Booster Free Version is designed to make your computer run faster and crash less often. It can optimize RAM to make your computer run faster and crash less often, increases your system performance by cleaning the content of your RAM