Yes with some modified settings you can use your pen drive as a RAM
1) Connect your pen drive to your PC [pen drive should be at least 1 GB or if you having 4 GB then its better]
2) Allow PC what he is supposed to do,let system to detect pen drive.
3) After your PC finished with its detection work,you have to do some little
4) Right click on the My Computer and select the properties
5) Goto advanced and then performance setting then advanced then
6) Select pen drive and click on custom size " Check the value of space available "
7) Enter the same in the Initial and the Max columns
" You just used the memory of the PenDrive as a Virtual Memory "
8) Now restart your pc and enjoy your fast and super system