I'm combining two great articles I read and spending an hour a night (plus what extra I can on weekends) and making a game a week.
Mainly I want to improve my gamemaker skills and get better at rapidly prototyping ideas. I work as a game designer and I can already see how this is helping me get out of lots of bad game dev habits that become a kind of necessity when you have to ship something.
I'm keeping a log book and so will probably post a few articles about it as I go.
Thanks!