Pretty much everyone I know is investing in trading virtual currencies and we are making a killing. You do not want to be buying BTC/LTC, not unless you have a ton of money to really make a decent profit. Right now the currencies offering the best returns are PPC/NMC. The best time to buy is in the evening when the prices drop to like $5.5/PPC and then during the day rise to 7.5/PPC, a good $2 return per coin. Invest $1k like right now when an exchange such as btc-e.com lists PPC for $5.5, gives you 1000/5.5 = ~181 PPC's, then sell during the day when trading picks up, prices rise to about $7-$7.5, and you can make ~181 * $7.5/PPC = $1363 - $1000 in expenses = a return of ~$363 to give you an example (Not including trading fees). During the day the trick is to time things right so you buy as many coins as you can and try to gain $0.10 to $0.20 or $0.30/coin.
The problem with LTC is it's too expensive for smaller people, but the same trick applies during the evening. If you have a few $k to invest, it would be wise to start investing before too many people beat you to it. I just wish I had the guts to invest a few $k more than I am now. It's still a gamble but as the days go on I'm learning more tricks about working on each exchange.
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