HexVexed is a hex tile game that was never finished.  It started as a fork of Dark Wyrm's BeVexed.  This may be a challenging program to work on, but if you like programming and like puzzles, this might be a good one to pick.  The file hexgrid.cpp contains a diagram of how the tiles fit together and what sides need to match in order to solve the puzzle.  Perhaps start with Dark Wyrm's BeVexed and play it a few times to get an idea of how it's supposed to work. 

https://bitbucket.org/scottmc/hexvexed

http://darkwyrm.beemulated.net/apps/bevexed.htm

Here's a link to BeVexed v1.1 including the source code: http://darkwyrm.beemulated.net/downloads/BeVexed1.1.zip