To answer your question, it's a very very very good head rush with a bit of euphoria. It's like snorting coke, but much better. Smoking a rock will generally hit you anywhere between 20-45 seconds and will last about 3-5 minutes, depending on the purity and the amount of time you held the smoke in your lungs. I also find the best way to smoke it is to use a glass / metal rod with some char at one end...the rock with liquify then vaporize, and some of the liquid will drip down the inside of the pipe, but that's okay b/c you can adjust your char and reheat it. Addiction is funny: some people get it on some things, and others don't. If you're into stimulants, or if you'd had problems with stimulants in the past, I'd say your addiction potential is high, but that's not a guarantee. All in all, unless you have a lot of money to spend or are friends with a dealer who will hook ya up below retail price, crack isn't really worth it. Sure, try it, but after you do it you're only gonna want more and more, especially for the rest of the night.