There are a few new alt coins that pop up every now and then, which run on different algos so GPU miners stand a chance. Check out the ANN forum to see.
No altcoin is worthy enough to mine yet except for the ethereum, specially with the graphics card. If you try to mine any other altcoin, you'll make some loss or if you get some profit, it'd be half of what ethereum would provide (I've tried many alts other than ethereum).
If you have a few GH/s mining hash power for the ethereum, and you move your rigs to the altcoin, you can easily 51% attack that.
