How to free up memory used by firefox

Mozilla Firefox is the most popular web browser on the internet and has loads of customizations but it is also known for hogging up memory resources over time. Sometimes it takes up almost 300 mb - 400 mb of memory when you surf a lot. Mostly this is due to the loads of extensions that one adds to customize it. Though Firefox 3 claims to solve this but until it is released we are all stuck in version 2. So here is how to do it.

Step 1: Type about:config into your location bar and hit Enter.

Step 2: At the top of the page, in the Filter text box, type browser.cache.

Step 3: Double-click the "browser.cache.memory.capacity" entry. The default is 50000. You can reduce this further to let's say 15000, then click OK. Try not to go too low, 15000 seems to be a good number for those with 512MB/1GB RAM.