T-Mobile is offering 10,000 Delta miles over the course of your first year.

Subscribe to an Unlimited National Annual or Month to Month subscription plan and earn up to 10,000 miles over your first year of service by earning 500 miles per month of paid service and 2,000 bonus miles for every six months of paid service.

This is better than the standard 5000 miles they’ve offered, though not worth signing up just for the miles. If you’d subscribe to T-Mobile anyway, I haven’t seen a better bonus.