Any Xbox purchase at Walmart will get you a $50 store gift card. That's a good deal on its own, but the bundle deals available on their website are downright unbelievable. Plus Sears has a 12-month Live subscription for $20:
For either $260 or $360 (depending on if you get the Arcade or Elite), you get:
• An Xbox (duh)
• 2 games (including selections like Modern Warfare 2 and
Left 4 Dead 2)
• 12 Months of Xbox Live
• A $50 Walmart gift card
By my math, that's about $160 of stuff (assuming two $60 games and $40 for the Live sub) thrown in for $10 over the price of a barebones Xbox (if you subtract the value of the $50 gift card from the bundle price).
If you've already got an Xbox and need to renew your Live subscription, Sears has a 12-month sub for $20. That's the cheapest I've ever seen it. Update: The page is down, but if you search for Xbox Live it pulls up a $20 price. Maybe you'll have some luck printing it out and getting the deal price matched in-store.