I like your ideas about this. My client actually implements your 2nd suggestion already. One thing I don't really agree with is your first suggestion (grouping).

Grouping has its benefits, but you need to be able to select which groups you prefer, per search request or session. Say that I am sharing nothing but MPx files, grouped with others sharing MPx files. But, what I need is a DOC file. How large is the chance I will actually find that DOC file in this group?

Your last suggestion is something I've proposed quite a while ago on the GDF ("piggyback riding"), but it didn't really catch on then. However, a new proposal called GGEP, or a special extension that can be attached to all Gnutella messages, will allow us to do this much better.

Cool stuff. Keep it coming

-- Mike