Err, if I'm not mistaken, Windows does that all the time on it's own. That's what happens when your physical memory gets full. there might be some program that'll do it in a more organized and better way... not sure.
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CPU: P4 3.0GHZ Prescott HT @3.6][MB: Asus P5LD2][RAM: 1GB][Video Card: ASUS EAX800/ I.E. Radeon X800 256MB][Optiwrite DVD+R/RW 8x][40GB WinXP SP2-OS][250GB SATA Storage(Full)][120GB EIDE Storage (Full)][160GB Sata Storage][And one badass case!]