Steve, your October 2007 viewing of all the (then) nine planets (including Earth by astroron's sensible direction!) must have been a buzz, and very well done. Yes, perhaps asteroids are the next targets!
I note that it took at least a 9-hour span for you to achieve the planetary viewings, but it's obviously possible to do it in less time, as in my recent 5-hour slot. (Pluto was in fact well-placed if I'd had the gear and observing experience to be able to pick it up.)
However, as you say, locating Pluto is a completely different level of difficulty, and I'd restricted my relatively easy challenge to just eyes and binoculars.
StephenM did this in a similar time (but used a dSLR to 'retrospectively' identify Neptune on the computer screen … hmm, not sure that counts!
).
So, has anyone else viewed all eight planets Mercury to Neptune (including Earth!) directly by eye/binoculars in a shorter time period?
Alternatively, does your planetarium program suggest any amazing viewing opportunities … past, present or future?