I do basically the same thing, and have for years also. My only frustration with this is that with some sites, due to arcane password restrictions, the algorithm either isn't implementable, or is only implementable in such a way I won't remember. So 90% of the time the strategy works great, and in 10% of the time it fails due to idiosyncracies of the sites involved.

I hate the stupid restrictions sites place on passwords. There should be almost no restrictions.