I voted Tory because Labour massively over borrowed during their time in office (and kept the full extent of their borrowing off the books using PFI) and seemed to be deluded about the fact that you just cannot have everything. The banking crisis, while pretty awful (but predictable), is a separate issue from the massive government overspending that took place before the crisis.
I am not parroting something I've read in a newspaper when I say this - our extended family contains three economists, and out of interest we looked at government spending and did some rough sums together a couple of years before the banking crisis. We concluded at the time that spending was unsustainable and that the shit was going to hit the fan at some point. We also looked at the housing market and predicted that there was going to be a crash (which was why I didn't buy a house!). At the time, we didn't factor in the American sub-prime industry, otherwise we might have predicted the financial crisis. (FYI we still think there's going to be another house price crash.)
Cameron does not strike me as an ideologue in the same vein as Thatcher, and I think he (and the reality of working in a coalition) is capable of keeping that part of the Tory party in check. I think people who say things in the vein of "nasty Tories just want to cut everything and make poor people suffer" need to ask themselves why any politician would do anything so patently unpopular if they didn't need to.
In addition, I am naturally averse to voting Labour as the Labour party and many Labour voters in the part of the country I grew up in were the worst kind of unreconstructed misogynists you can imagine and I find it very hard to see that Labour has anything to offer me as a woman. I also opposed identity card legislation on libertarian grounds and I am sympathetic to repealing the ban on fox hunting, again for libertarian reasons (although I do not hunt myself and don't know anyone who does). I felt strongly enough about identity cards to vote Tory on that issue alone.
And I wouldn't be considered rich by the OP's criterion.