There are times when I would like to use most of the available memory to run a particular program. But after running several programs, I find out that i'm running low on memory, even if I already closed the programs. Is there a good program to free up the memory so that I can run a memory-hungry program, say, my Command and Conquer Generals?
Thanks in advance!

well... you might want to start with killing a bunch of Services you don't need.... go http://www.blkviper.com/WinXP/servicecfg.htm to find out how...

There are utils like RamIdle Pro from /http://www.tweaknow.com/
and CacheBoost from /http://www.systweak.com/cacheboost/default.asp
and a whole lot more alike theese two. I guess this is what you are after.
There are pros and cons at the same time using them, go download a trial and find out.

I just learned that System Mechanic 4 has such utilities. Check it out at www.iolo.com