I've been tinkering around with the battery packs and have made 2 of my own using 850mah AAA nimh batteries I got off ebay.
they give longer flight times without adding weight. I need to make proper connectors for them, I am using standard blade connectors right now.

Does anyone know if you can make your own blades? I looked inside my first set after I smashed them, and there is a soft lead strip in them, on the end of the leading edge, I have already cut out a rough shape of them in balsa wood and will try to coat them in diluded glue to stiffen them and then I guess cover them in packing tape or just monokote, I figure if I can do this, I should be able to save approx 15-18 bucks (canadian) cause new ones are $20.