So far as I know, you can't re-install a software that you got from the giveaway site as it "gives away" the tool for installing only on that day. So, even if someone gives you TweakRAM, you probably, and most definitely I guess, cannot use it.
Anyways, why don't you try RAMpage? I forgot the website but one can always Google.

Just got the site: RAMpage - Freeware memory monitor/memory freeing utility
It uses minimal mem itself and gives a tiny black-green digital display on your systray.
The tool is opensource.