This little script I picked up here (and modified just a little bit) makes it easy to make a Fritzbox reconnect it’s DSL-connection. It works fine with my FRITZ!Box Fon WLAN 7170 at firmware version 29.04.49.
There are some really nice hacks out there for the Fritzbox, like the DS-mod and other stuff, but at the moment I like the box just like it is (remote WoL would be a nice thing though) and having a 2 year warranty also is not a bad thing.