Unsecured lending to individuals is not, in general, a "safe" investment. Lending Club hasn't even been around long enough to reasonably estimate how safe it might be. Note that I'm not claiming it's a bad investment, but it really stretches the traditional financial definition of "safe."
And the highest I've ever seen for high yield savings accounts was around 6%, generally only for a promotional period, around 2007. Unless you're talking about the high inflation years in the late 70s and early 80s, in which case, yes, you could get 10% in a savings account, but the real rate of return was well into the negative due to inflation.
That may be true, but safe investments generally pay less than that. Lending Club might be a good investment, but I'd think of it as a peer-to-peer credit card, not as something that competes with T-bills and commercial paper.
i use lendingclub.com http://en.wikipedia.org/wiki/Lending_Club
during less severe economic times you could also make around 10% via high yield savings accounts