Magic the author of a new dreamcast emulator for PC has just emailed me informing me he has released his emulator DCPC:

The emulator doesn’t boast great compatibility or any of that. At the moment it just loads the bootstrap and has a simple debugger, although the Sh4 core is dynarec it is VERY fast, memory emulation is lacking somewhat so demo’s aren’t going to work for sometime, a detailed account of the project can be read in the readme.

You can download this new emulator here