We all want to increase our new computer's performance with minimal cost. Here's one low cost and simple way to do it: enable ReadyBoost in Windows Vista - which uses a USB Flash Drive to supplement your computer's main system RAM memory.

The smallest cache that ReadyBoost can use is 256MB, and the largest at 4GB. Since prices of a USB Flash Drive has gone down considerably, you can choose to buy for example an 8GB Sandisk Cruzer ReadyBoost Compliant USB Flash Drive for just $54.99 AUD, and allocated 4GB for ReadyBoost and keeping the other 4GB for your own essential files.

According to official writings, it is important to ensure the USB flash drive is ReadyBoost-ready and compliant. Those brands that have been fully tested would have an indication in their product. E.g. Sandisk Cruzer U3 ReadyBoost and Sandisk Cruzer Titanium ReadyBoost.

Simple Step-By-Step:

1. To enable ReadyBoost, after plugging the USB flash drive into a USB port, a screen will appear, then choose "Speed up my system". (Remember this is for Windows Vista Operating Systems only)
2. On the next screen, choose "Use this device", and click OK.
3. On the ReadyBoost tab of the device's Properties dialog box, specify the amount of space you wish to allocate.

More notes:
Microsoft's official recommendation is a ratio of between 1:1 and 2.5:1. So if you have a PC with 1GB RAM, you ought to allocate 1GB to 2.5 GB for ReadyBoost.