imp-pcap-filter.pl 
- uses Net::IMP to manipulate pcap stream, e.g. reads pcap data from file
  and writes new pcap file
- very useful for testing IMP modules with deterministic input
- does not support IMP_TOSENDER result

imp-relay.pl
- relay (e.g. proxy, application level gateway...) with IMP module support
- destination can be set fixed
- can also work as a socks4 server to extract destinations
- will probably work transparently too (not tested)
- probably still enough bugs in it, so don't use it for anything else than testing:
  might leak memory, keep connections open..