These ones from ASOS seem particularly popular, but at £40, I don't think they'd last me very long as they're suede so will tarnish very quickly.
This version from Office only has suede on the top half, so probably more hard-wearing, and they're £45.
But when I was in H&M this week I spotted a very similar looking pair of flatforms which are also only suede time material on the top half, and cost quite a bit less at £24.99.
I've not taken the tags off yet as I'm not certain that these are actually all that comfortable - a few wanders around the house are necessary before I can be sure I think.
I can't link to these as they don't seem to be on the H&M website yet - I picked them up in the Oxford Circus branch.
What do you think of flatforms?