I do have a whistle on my keychain, but it's a Fox 40 Micro. It's not a "self defense" item either, it's a search and rescue type of idea, beats the crap out of screaming in the middle of the woods for hours.
So me and a couple buddies checked out The Expendables today (ok, yesterday...) and I gotta say, I was not disappointed. Sly knows how to do an action movie. Not so over the top as to have you saying "yeah right" through most of it, but enough to make it flashy and fun. My only complaints are that their carbines could have had more and clearer screen time. All I could tell was they were 11.5" AR types with Noveske KX3s on the end (and with crap-tastic GI mags... you'd think when your buying your own stuff you'd get good mags...) That and the guy with the AA-12 burned up all the profits with his gratuitous use of the mini-grenade rounds.
All in all, if you like Rambo-esque action films, get to the theater.