As far as shmups (shut-'em-ups in Old English) go, Ikaruga by Treasure must be one of the best and most influential games ever released. As for its relatively rare Sega Dreamcast edition, well, besides offering the standard amazing visuals and polarity gameplay, it also commands some impressive ebay prices. Well, at least it usually does. Better have a look at this Ikaruga Dreamcast (jpn) auction. The current bid is only 5.5£ and the seller ships worldwide.