If you have the room, I think it is a good idea to have at least two projects!
I have nothing major right now (and NO time to start something!), but the side project I have is a Uravich Fokker D-VII that I tinker with when I get burned out on other things. I am sure it will never be done, and I will probably never fly it. I don't care. It would leave me in a quardry for another "side" project if I ever DID finish it!
Mace Gill
The Aeroplane Works
http://www.theaeroplaneworks.com