There are some programs out there that would clean out more memory than MemMaid. e.g. sktool. There's another free one, can't remember the name, but has an awful icon that can clean pretty good.
However,
These are just temp solutions because it will never give you back all the memory.
So, you need to hunt down which program(s) is giving you the leak.
Do you have a program (e.g. magic button) that would actually close your program instead of just "minimize them"?
If you do, then you want to look at you today's plugins, what do you have there?
Hope this helps, it's going to be a lot of work.