Kitbashing and building your own plane from scratch is the most
rewarding part of the hobby.
Some examples are shown here:
[link=http://www.rcuniverse.com/forum/m_5244036/tm.htm]aa mods[/link]

I've been working on a blog for the AA that will go into some detail as to
how to build peanut sized RC AA's. It should be up in about a month, just
in time for the summer flying season.