Be warned that Bitcoin as a whole is still a pretty woolly area legally. The law wasn't ready for it, there's a lot of uncertainty, and there are, predictably, scammers and fraudsters trying to take advantage of that uncertainty.
It's been getting better lately as the law catches up a little and figures out how to do their jobs here. But the scammers are still around. Making a bet that they're planning how to get you to "invest" your money in their next house in the Bahamas would be a pretty good investment.
That said? An investment in mining could be a good idea if and only if you live in an area with heavily subsidized electrical utilities and/or can work out a sweetheart deal that gets you at least a 50% discount on electricity. Some people are installing bitcoin miners as electric heaters in chilly areas, which gets them free electricity out of what homeowners or business owners are willing to pay for utility costs for heating. Otherwise, mining reliably loses money for two reasons. First, because you're competing with people who do their mining in exactly those conditions. And second, because at least a few of them are deliberately mining at a loss, either as an expensive way to speculate on a future price rise or as a premium they're willing to pay for the "virgin coins" they mine, which have no transaction history whatsoever and, if spent carefully, cannot be traced at all.
Ummm, yeah, that probably means exactly what it sounds like it means if you're paying attention. Like I said, you should be very careful about whom you do business with and what business you do, because the law is catching up and the sort of people who are likely to come to their attention are by no means gone.
An investment in Bitcoin startups would be best for the community as a whole, but for the investor it's a risky play. Could be astoundingly lucrative depending on what happens, but.... I guess it depends on how much money your coalition has to invest in the *whole* portfolio that determines how much you can put on something risky.
Probably the most reliably profitable, least risky, and lowest-margin bitcoin business right now would be a currency exchange. Right now there are dozens of players trying to be currency exchanges - and federal money transmitter laws are removing many of them from the business, so if you can navigate that legal maze the competition is getting weeded out for you as we speak. But on that score you'd have to act pretty fast, because there are already some big players moving. It's not just the Winklevii either; there are some sharper, faster-moving businessmen in some of those startups.
Second on the list is people who supply payment services; Joe merchant wants to accept Bitcoin at his truck stop bar & grill, but doesn't want the bother and complexity of managing it himself. Payment services guy steps in and sets him up with the appropriate secured equipment, shows him how to use it, processes payments for him, etc. Bitcoin here is a competitive advantage over Visa etc, because the per-transaction costs are lower. That is, the bitcoin-to-bitcoin transaction costs are lower. If you're paying an exchange to convert to and from other forms of money, you'll want to aggregate bitcoins to make fewer and smaller tx at the exchanges. Or, you know, do vertical integration and be the exchange as well as the payment services provider.
