aBridge is a bridge game that allows you to play bridge online with other real people.
At the moment, aBridge runs under linux and windows, and you should be able to use it to play bridge without too many annoyances. However, aBridge is still lacking a number of features I would like to add, and has many minor bugs. If you are interested in helping improve aBridge, let me know!

License: free

Additional System Requirements: