Believe it or not, it's possible to take a photo of Jupiter and its Galilean moons w/o a telescope! I have a Pentax Lumix camera, 5 Megapix, 12x optical zoom, that goes up to 8 sec exposure. On Wednesday night here at Astrocamp, I set it on a table (b/c I didn't have my tripod with me), zoomed as close up to Jupiter as I could, put it on 2 sec timer so it wouldn't shake as I pushed the button, and bracketted from something like 0.5-8 seconds. The longer exposure got the moons further away as streaks, the shorter exposure got the closer moons as fuzzy blobs. When I got home I cropped like crazy, but didn't do anything else to alter the images. Imagine what I could've done if I'd had an SLR with a longer exposure.
Outer moons; Callisto on left, Ganymede on right.
Inner moons; Europa on left (closest), Io on right (farther).
Moon positions are from the Juplet java applet. Over the course of this week I was able to watch the moons zipping back and forth, it was pretty neat. I'm gonna see if I can take some more next week and track their positions throughout the week.