> numbers, then you could have source kept in a proper database. Like, say, dabble. Or a dabble-ish thing that kept recent-ish stuff local and
> could refer back to a server for ancient history. Find all versions of a method back to the beginning of time...

The all-method-history thing has been available for a while now via Magma.

   http://wiki.squeak.org/squeak/5603