"Some 40,000 Danish car owners are about to become mobile promoters of the Danish People’s Party (DF), and not all of them are too happy about that. After the changeover to EU licence plates last year, the two-letter, five-number combination is approaching “DF”.
The DPP is a eurosceptic party allied with UKIP in Europe, so it is hardly pacing around the outer limits of respectability. Meanwhile, "Letter combinations such as DK, EU, UN, SS and KZ are not permitted on Danish licence plates". (KZ appears to be the German abbreviation for Konzentrationslager, or concentration camp).
I have just had a look at the DVLA's site, and one can buy SWP, but not B*P. I believe J1HAD was banned some years back. Other finds would be most welcome.