Many special editions of the Dreamcast were released over the years, in a variety of different colours. However, every special edition Dreamcast that I've seen has had some other visual change besides just the colour.
Looking at the pictures, I suspect that your console has just been put into a replacement aftermarket shell. However, if the bottom half of the console is solid grey, and there's a pale yellow limited edition number sticker on the back, then you have a quite rare Code: Veronica (Claire version) console. I'm guessing that if the sticker was there, though, you wouldn't be here asking about it, as it's a real giveaway.
That being said, it still looks cool, but I don't think it's going to command an especially high price or anything. The controllers were always available in a wide range of colours, although it's funny that the beige controller on the right has the blue European swirl. I guess someone got a deal.
