Apps similar to FreePastry include Chordless, which is free and open source. Other options are Open Chord and NChord. In total there are three apps like FreePastry for Mac, Windows and Linux.
Chordless is a Chord and DHash implementation written in java. It implements almost everything from Chord and DHash described at http://pdos.csail.mit.edu/chord/ , as well as some extra features such as transactions and remote method invocation.
OpenChord is an open source implementation of the Chord distributed hash table as described in the paper by Ion Stoica et al. "Chord: A scalable peer-to-peer lookup service for internet applications".
NChord is a C# implementation of the Chord distributed hash table. The project provides a library containing the routing, lookup, and maintenance routines specified in the MIT Chord paper, and is quite stable including under heavy load and churn.
