Lava miner
I spend around 45 mins on this one. It was hard figuring out a way to make those smoke light effects in less than 10 min. I was going to post it on Daily Spitpaint, but rules are rules.
I also recorded the whole process (10 mins, speed up version), so if you like you can check that out here (opens in a new tab). Also, sorry if the screen ratio is in 4:3, the monitor I worked on was kinda old.
Photoshop CS5, mouse
Around 45 min.