I'm pretty sure it's Asatru and other religions that follow Norse Paganism that have the belief that if you die in battle you go to Valhalla. And it's pretty much the prime place to go.

Is that still practiced today? I mean, today's equivilent would be joining the Army and being sent to a conflict.

Do you literally believe in Valhalla?

Asatru is still in practice today, yes.