Not all routers support all information or actions. I have added as much information as I thought needed and was able to figure out how to add without actually owning the router. If you find that something does not work but is listed as supported on this page, feel free to contact me. If your router is not supported, read this.

Generic Firmware

DD-WRT v23/v24
External IP, Uptime, Memory Usage, Load Average, Connections, SSID, Channel, Clients
DHCP Renew, DHCP Release, Reboot
Tomato
External IP, Hostname, Uptime, Memory Usage, Load Average, SSID, Channel, Clients
DHCP Renew, DHCP Release, Reboot
OpenWRT White Russian
Uptime, Load Average, Clients

Linksys

BEFSR41, BEFSR81, BEFSX41
External IP, Clients
WRT54G v1-v4
External IP, SSID, Channel, Clients
Reboot
WRT54G v5-v8, WRT54GL, WRT54GS, WRT54GX v1
External IP, SSID, Channel, Clients
WRT150N, WRT300N, WRT350N
External IP, SSID, Channel, Clients
Reboot

Netgear

FVG318, WGR614, WGT624
External IP, Uptime, Clients
FVS318
External IP, Clients
Reboot
WGT634U
External IP, Uptime, Clients
Reboot
DG834G v3
External IP, SSID, Channel, Speed
Reboot
DG814
External IP, Speed

D-Link

DI-500 Series & DI-600 Series
External IP, SSID, Channel, Clients
Reboot
DIR-655
External IP, SSID, Channel, Clients
Reboot

Random Brands

Allied Telesis AR-410
External IP
Reboot
AVM FRITZ!Box Fon WLAN 7050 (DE)
External IP, Uotime, Spoeed, Bandwidth
Edimax BR-6104K
External IP, Clients
Reboot
Level One FBR-1407A
External IP, Speed, Uptime, Clients
Reboot
Quidway W1003a
External IP, Uptime, Speed
Sitecom WL-160
External IP, Uptime, SSID, Channel
Reboot
Verizon Actiontec MI424WR (FIOS)
External IP, Uptime, SSID, Channel