Profit / Currency Exchanges

Hi,

I'm obviously new here, and there's one thing that's been gnawing at me:

If you can put together some equipment that can do GPU mining for scrypt-based currencies, and even the most alternate of alternate coins can be mined pretty aggressively while the difficulty is still low, and you can generally exchange the wild currency for something less wild, eventually making your way to one or more bitcoins, isn't there a lot of real world money to be made at very little cost? I suppose each new(er) currency becomes prohibitively more difficult to mine quickly enough that it's like chasing a moving target, but the math of the thing just seems to suggest there is a ton of opportunity here, even for the little guy.

Am I missing how this breaks down and ends up not being worth the effort?

Thanks,

TL