Building a TikiWiki cluster
It's really easy. Get 2 machines that are well connected. I have 2 root-servers at server4free.de. Install tiki on both machines, but the mysql db only on one. Direct the mysql connection of the other machine to this one. In Admin->General, set to save the Session in the Database. Then create multiple A records for the Servername (e.g. redflo.de) with the different IP's in your DNS zone file.
redflo.de. 600 IN A 126.96.36.199
redflo.de. 600 IN A 188.8.131.52
If you'd like to have the modified cluster-aware who-is-online module (top right), then contact me. Probably Tiki 1.9.1 will have the module.