Well I read Routing TCP/IP's chapters on EIGRP, and have been labbing quite a bit out of Narbik's soup to nuts lab book. Great book btw. I even recorded my session last night using Camtasia. I will try to figure out the best way to embed the video in the blog here.
One of Narbik's tasks was to inject a default into the eigrp domain without using a global command, or a router configuration command. Honestly, I was stumped... Heres the brilliant solution.
(config-if)ip summary-address eigrp 100 0.0.0.0 0.0.0.0
Thats it! It sends the default to the neighbor, and they send it to their neighbors. Worked like a charm.