As of this posting, Keggle Brewing has four packs of 5 gallon racetrack style ball lock kegs for just $100. That figures to $25 per keg, no coupon code is required. Shipping is an additional calculated fee based on your location. Check Keggle Brewing for current selection, pricing and availability.
Also Consider: Keg Connection Keg Sales – sorted to show best selling first – flat rate $7.99 shipping is also available
Related: Recent Keg Finds on Homebrew Finds