Well it looks like the DVLA were out early this morning in Birmingham.
Whilst popping out to the shops i spotted at least FOUR cars with wheel clamps courtesy of the DVLA (plus paperword stuck to the windsceen) within a few hundred yards.
I did a quick check on one of them (half parked on the pavement), and sure enough - no tax or MOT for over six months.
I certainly don't live in a deprived area, so was quite surprised how many there were (and probably loads more in the surrounding streets)!