Hi,
Is anything like that available or in the works, or is there some alternative I'm not aware of?
Maybe, you could try the UbiquiTalk platform :
You could also try Discovery framework. http://map.squeak.org/package/6a54b2cc-ea9b-4622-a0cb-fd7222c22892
It is used in SuperSwiki2 for detecting local SuperSwiki2 servers in LAN. http://swikis.ddo.jp/SuperSwiki2/3
Cheers,