My laptop, go figure. I should have gone with Fargo's instinct and clung to my glasses, though I guess one usually doesn't expect a 'no clothing' rule.
I was going to say 10, seeing as a laptop is exceedingly useless in this scenario... but then I realized I could probably take it apart and make the battery into a crude sparker. That should help me start fires long enough to get some practice doing it myself. After that, it's a matter of scaring off the local wildlife, razing the land, scraping together some stone tools and starting an agricultural society of one.
A velociraptor probably wouldn't know what to do with a mammal of my stature, but it's still a bit of a long shot since I don't really know how to make a water skin. I'd say about 6 or 7.