I bought one of the several lots of annual mugs at auction yesterday, as it's always good to have a few in my store on eBay and they seem to maintain their popularity as gifts, and for collectors etc.
One I haven't had or seen before is the 1980 version, designed by Anne-Marie Trolle, who also designed the 1976 pattern which was part of the group. (1976 seems to be one that is always comes up at auctions - it must have been a very popular year! )
The other special one I picked up was the 1967 Nils Thorsson design - which was the first ever annual mug from Royal Copenhagen - and as with all first editions it is quite valuable compared to all the others. Currently sells around $300-$350 ...when it comes up. The design of it always reminds me of "I dream of Genie" - must be the minaret shapes or something :)