In message , The Last Danish Pastry
writes
Some questions:

To what extent are there other transits in the solar system? For instance,
how often do these happen...

A transit of Earth as seen from Mars?
A transit of Jupiter as seen from Saturn?

Also, when is the next total eclipse of the Sun which occurs during a
transit of Venus?


I'll leave the transit of Jupiter to the experts :-) but the last
transit of Earth was on 11 May 1984, the next one is 10 November 2084
(thanks to Jan Meeus for predicting it and Arthur Clarke for writing a
short story about it)
Thanks to Jan Meeus again we know the next transit during a total
eclipse is on 5 April 15232. There are several transits of Mercury
before then (source is the Journal of the BAA volume 114 June 2004)