I trade Doge/Netcoins/TAG/Protoshares/etc for BTC directly, but I just as often wait for the market value to dip, like now, and buy. Taking advantage of the pump & dumps will net you a fair amount more profit than just mining alone. The only downside is that it's fairly time consuming, because you have to keep a close watch over the market prices. It's also a bit more risky, due to needing funds on hand at the exchange to be able to buy at a moment's notice, vs. the lag of transferring from your wallet to the exchange, given the exchange(s) history of being compromised through hacking (or in some cases, by their outright theft).
Ofc, the trading game can always bite you in the posterior if the market value flatline's permanently too...
I use Bter & Coins-e mostly, for my trading of Alt's.
Edited by ForceProjection - 12/27/13 at 11:55am