How about contributing to an the Visual Component Framework - you could take the work I started in the RemoteObject Kit and turn it into a pretty cool and useful project (does distributed objects in C++, but with no IDL, allows for dynamic object introspection, dynamic methods, etc). Or if you're interested in something visual, how about helping with the VCF Builder, a GUI builder like VB or Delphi, but based entirely on the VCF. For more info either email me, or check out http://vcf.sourceforge.net, or http://sourceforge.net/projects/vcf.