Google havelock investments. They sell shares to many bitcoin companies. BTCjam also offers a place like that, where you can make a nice 20% annually.
I have heard bad things about BTCjam, it is populated by scammers. They take out small loans, repay them to get good ratings, then take out a big loan and walk away. Rinse and repeat under a new username. So the site reports something like 75% repayment rate (I don't know the current stat), but the 25% that are not paid back are much larger loans than the ones that do get paid back. Basically, from an investor's point of view, it is a good way to lose money.
Have you had a look at
mpex.ws as a place to invest?
I doubt any serious investor would pay MP 30 BTC to be able to trade heavily manipulated stocks with very little real value on his mpex exchange.
BTCjam had bad payback rates back when it started but it has been getting better since then and way more borrowers that defaults ends up having there assets & salerys seized by courts these days to repay there debts.
The repayed/overdue factor for BTC over all time was up till june 2014 2.09 or if you so like 67.6%, if you look at the 12 month period july 2013-june 2014 the factor was 6.93 or 87.4% and for the 6 month period 1 jan 2014- 30 june 2014 11.24 or 91.8%.
Repayment rates for BTC is better than if you compare it with the number of loans repayed/overdue so your wrong about that part to, the avg overdue loan is smaller than the avg loan in total, so most loans that is one or more days late on there payment is relatively small.