You read that right Volgarr the Viking has been ported to the Dreamcast. This is an unofficial port by one of the developers.
From the developers:
This port of Volgarr the Viking was not created by Crazy Viking Studios, but it was created with their full permission and access to the original source code and assets. This means that Crazy Viking Studios does NOT guarantee the quality of this product, or even that it will work at all. Use at your own risk!
You can grab the game, cover, and manual here:
http://volgarr.rkd.zone/