Currently listing (though to be fair most are selling as soon as they go on!) are stamps from the Isle of Man, a small island in the Celtic Sea which lies close to England, Wales, Ireland and Scotland. The island had UK regionals from 1958 and became postally independent in 1973. There are earlier revenue stamps specifically for the island as well.
Reasonable amounts of stamps are issued each year and most issues are relevant to the island, which is distinct in many ways (from cats to trams) as is not part of the UK but a self-governing territory - in fact it has the world's oldest continuing parliament (Tynwald). Its distictive flag (the treskillion) shows the symbol of the island on a red field, the island issues its own currency (sterling, but with a Manx theme), it has its own language (Manx, a Celtic language, similar to Cornish, Welsh etc) and has a fantastic network of narrow gauge trains and trams, including steam, electric and horse-powered. It is an intriguing mix of the best of England, Scotland, Wales and Ireland, but is also distinctively Manx.
All in all a fascinating country to collect, and there are few if any expensive stamps.