I go through phases of enthusiasm and the blahs. It helps me to think in terms of baby steps. I try to envision a finished project and calculate how long it would take if I only do an hour a day, or even just 15 minutes. Once I see progress I usually get a little momentum. It's not something I do because I have to, but the UFO's represent a considerable investment in time and money, and that nags at me. Paradoxically, if I let myself get too disappointed in myself for not achieving what I set out to do, then it's easy to start spiraling downward and get nothing done for weeks.