Giestheld is hashed with cpu only?
No, you mine it alongside bitcoins, namecoins, devcoins, etcetera, all the other merged mined coins, using the same rigs and the same power-bill. You or someone else already pays for the electricity, you might as well rake in all the coins it can rake in instead of "leaving money on the table".
If you want to mine with a CPU your best bets might be Tenebrix and Fairbrix, though I think sometimes some people (such as myself from time to time) point a 5870 in balanced mode at the two of them, if difficulty compared to number of connections is high enough to indicate other people must be using a GPU instead of a CPU on them or are maybe using a lot of powerful CPU cores.
Of course if you have lots of very powerful CPU cores you might prefer to point them at primecoin or (if you have really many or really powerful ones) even at protoshares.
Understand that by unknown crypto I assume you mean under the radar, not on exchanges, likely not even on any pools or merged mining pools, so that you can mine it incredibly easily month after month, maybe even a whole year of CPU mining like people had with BBQcoin, so that by the time the masses remember it exists you have a nice stash of them so you can afford to act as a market-maker when they do appear on an exchange, buying low and selling high, making a fortune providing liquidity...
-MarkM-
