We all heard of Microsoft's new OS - Windows Vista. It brings many new things. Including ReadyBoost. Let's see... you want to speed up your PC? You can't afford some hardware changes? You have Vista? Here's something for you. ReadyBoost. ReadyBoost is used to cache some files on your flash memory (flash memory on a USB 2.0 drive, SD card, CompactFlash, or other form of flash memory). With ReadyBoost, random disk reads with performance that is typically 80-100 times faster than random reads from HDDs. This caching is applied to all disk content, not just the page file or system DLLs.
Requirements
- The capacity of the removable media must be at least 256 MB (250 after formatting)
- Devices larger than 4GB will have only 4GB used for ReadyBoost
- The device should have an access time of 1ms or less
- The device must be capable of 2.5 MB/s read speeds for 4 kB random reads spread uniformly across the entire device and 1.75 MB/s write speeds for 512 kB random writes spread uniformly across the device
- The device must have at least 235 MB of free space
- NTFS and FAT32 are supported
- The initial release of ReadyBoost supports one device
How to Use
1) Plug in your flash memory device (I'll plug in USB 2.0 flash memory)
2) Go to Computer
3) Right click on your flash memory device

4) Click on properties

5) Go to ReadyBoost menu
If you can't use ReadyBoost on your flash memory, you'll get a menu like this:

My flash memory is loaded now (as you can see) and I can't use ReadyBoost currently.
If you can use your flash memory for ReadyBoost, you'll get this (I have to use Microsoft's screenshot
now).

By default, Do not use this device will be selected. Now, you select Use this device like in screenshot (but previously check how much space will you give to ReadyBoost to cache files on your flash memory). Click OK. You will probably have to wait a few seconds. ReadyBoost is ready! When you enter your flash memory you'll see ReadyBoost's icon there. It looks like this:

Close the window and work what you want
Your system will be faster. You won't notice this on apps which don't use much resources.
How to Turn Off
1) Go back to Computer
2) Right click on your flash memory
3) Properties
4) Go to ReadyBoost menu
5) Select Do not use this device
6) Click OK
7) Wait a few seconds
8 ) Done!
Now you can again use the space you gave to ReadyBoost for storage. I think you can unplug the flash memory without turning off ReadyBoost and Windows will automaticly turn it off. I am not sure will Windows turn it off (I've never tested it) and I highly recommend you to follow the procedure (sorry for bad spelling) I wrote. You may use your flash memory normally again!
I think you enjoyed in this short guide how to increase your system's speed 
Regards,
sosoe222