MythOS

Computer savvy sorcerer Ravirn learns that not every world is user friendly in this WebMage novel from Kelly McCullough.
In the 21st century, magic has advanced with the times and gone digital. Ravirn--umpteenth great-grandson of one of the three Fates--is a talented sorcerer, a computer hacker extraordinaire, and in the process of becoming a minor demi-god. His best friend and familiar is both a goblin and a laptop, changing shape from one to the other as needed.
While repairing Necessity (the badly-broken sentient computer that runs the multiverse), Ravirn is thrown into a very different place, a parallel world where the Greek gods are only myths. This strange realm is ruled by the Norse pantheon of gods--Odin, Thor, and other fun-loving brutes--and their magic uses a completely different operating system. A system that Ravirn will have to hack if he ever wants to get out of Asgard alive...