In addition to myfootballclub and Save the Victory, there are a couple of other options out there if you want to get a piece of a soccer club.
Fan Power points to myBUFC and BuyaClub.co.uk. MyBUFC is trying to buy a low level club in England. The advantage is they only need 5,000 investors (instead of 50,000 at myfootballclub and at most 20,000 with Save the Victory. The level of entry is also lower at about $50 for their non-league club, compared to about $70 at myfootballcub and $100 Save the Victory.
BuyaClub seems to be an almost exact copy as myfootballclub, but they're having a harder time getting people on board. Probably because they're asking for the money up front.