Blacktailed rattlesnakes are the best. They are usually so chill, that it's possible to get a few pictures before they try to get away. Also, I'm pretty sure I've never heard of an aggressive blacktail, so getting bitten isn't really a huge concern unless you're extremely stupid and reckless.

This picture was taken a few years ago at Ramsey Canyon. But with the weather getting warmer, I'm hoping I'll run into more snakes again soon.