If I remember correctly, Sheetcam requires Windows XP (has also been known to run in vista). Not sure about minimum ram requirements though.
Also, Les is developing a new version called Sheetcam TNG and it will have both a windows and linux version.
you can download the betas for TNG at his web site www.sheetcam.com.
I know what you mean about it being a timesaver especially for stuff with a lot of curves etc.