Firefox eats up my memory (RAM) like crazy. any help?

[Nathan]

I've been a long time Firefox user despite the occasional bug or hic-up, but this is different.

When I fire up Firefox, Task Manager says it's using about 300,000k of memory. However after some surfing (Facebook, Youtube, etc.) it piles up to 800,000k and sometimes as much as 1,000,000k of memory. How can I fix this? I have about 2-5 tabs open at a time, and have about 10 active extensions.
Tried using the Memory-fox add-on but it didn't seem to help much. I also did a reset of Firefox, but that didn't fix the problem either. Also tried many of the "about:config" tweaks that are found around the internet, but that didn't seem to help either. Any help?
My Windows 7 has 4GBs of RAM, which Firefox ends up eating most of.
And no I don't want to switch to Chrome or Opera, thank you.
I may do that Daniel, although Firefox has always used a lot of RAM for me even in previous versions.

I feel your pain Raj lol

Phil T. I have my cache set to 0 currently and it's still doing this.

Argus T. I have, and everything is normal RAM levels until I use Firefox for awhile, it steadily climbs in usage until it reaches 1,000,000k. Then I have to kill it because it's using too much RAM :/