Ubisoft has released free-to-play brawler Spartacus Legends on Xbox Live Arcade (that's "free" providing you have Xbox Live Gold, yes). Got two gigabytes of HD space to spare? Why not fill those gigabytes with screaming, bare-chested bodybuilders from Ancient Times? Queue up your download here.
"Developed in collaboration with the critically acclaimed television series from Starz, Spartacus Legends invites you to experience raw, visceral combat using multiple fighting styles and thousands of different weapon combinations," reads the blurb.
"Follow your gladiator's journey through multiple arenas and watch as they strive to reach legendary fame, or meet death at the hands of another. Compete with friends online and see if you have what it takes to kill them all."
The game is supported by real-money micro-transactions - you'll pay for new gear, mostly. Downloaders get a small pot of cash to start them off. Here's a trailer to wash everything down.
I'll add this to our continually updated list of free Xbox games, which you should definitely bookmark.