RE: What to do with my .049
I too have a box of old Cox .049's laying around. They're all that's left from the plastic planes I had as a kid. I have been thinking it shouldn't be too hard to mount one on the front of one of those styrofoam gliders you can get at the toy store. The ones that have about a 3 foot wingspan. Strengthen it with some of that reinforced strapping tape, modify the rudder and elevator to function, and mount a radio system with micro servos. You could cut the nose off flat and epoxy a thin plywood firewall on to mount the engine to.
Could be a fun, cheap-o plane to putter around with! Probably have to guess at the balance point though. But that's part of the fun!