Meanwhile, back at the ranch...

Some of us in the ham community have been using modified routers for things like putting internet access into bike ride rest stops and such (http://www.n5oom.org/hsmm/rootenna_project.htm). While we have been able to get links in at good distances, we had to fight with the bridge radios to make the links work. A few local groups decided to fix this problem, and HSMM-MESH was borne. This mesh networking system based on consumer grade equipment is still being developed.

http://hsmm-mesh.org/

I don't see any plan for using voice repeaters for any sort of data networking, but DSTAR digital repeaters are being pushed heavily for digital disaster communications.

http://www.dstarinfo.com/
http://en.wikipedia.org/wiki/D-STAR

This is a limited bandwidth system that runs on VHF and UHF bands, and can be used for point to point links of some distance.

Packet networking has been on the decline for a good long time, but more limited purpose networks have picked up.

APRS (Amateur Packet Reporting System) is useful for tactical vehicle tracking and messaging. APRS typically uses VHF (144 MHz) radios for local work. While driving to and from Mississippi after Katrina, we used APRS to track the members of our small convoy.

http://en.wikipedia.org/wiki/Automatic_Packet_Reporting_System
http://www.n5oom.org/aprs/index.htm (lots of presentations)

Winlink is a worldwide radio email network that uses HF and VHF radio links.

http://www.winlink.org/