Mod cc (Community Currencies)
This is an external package which allowed to set up basic Community currencies usage in Tiki 1.8, 1.9 and 2.0.
There is some information already and some screenshots at:
http://cc.tiki.org/Mod+Community+Currencies
This development was abandoned around 2006, and in 2010 a similar but extended feature has been added to Tiki6.