It’s been reported by VGN that Mike Daily is working on a C16/Plus4 emulator for the Dreamcast:

“Yep, at long last I’m about to start putting Minus4 onto the Dreamcast. This should be very cool. Frame rates should be 100% of the actual machine, scrolling etc. should be nice and smooth, just like the original! And best of all, it’ll come loaded with TONS of games! Right from bootup! Any of you that follow the Dreamcast emulation scene, should look at DreamSpec, this is the path I’ll be following. Easy to use, and plays games straight from the box! All you’ll need is a Dreamcast, and a CD Burner. Stay tuned for more as it happens! I’ll post piccys and news as I progress.”

Thanks to EvilN for posting this news on the forums.