The excellent blog Dropship Horizon is holding a 15mm sci-fi painting comp. Their post itself is pretty clear, but in a nutshell: three categories: squad, vehicle/mech, terrain piece. Must be sci-fi. You can enter one entry per category. Lots of prizes.
The comp closes in a month so, if you're me and your stock of 15mm figures is sadly depleted, time is a bit tight. But hopefully I can pull something together and even have the time to paint it nicely.