Of course, if you're looking for a serious answer, I always use Q tips and maybe a little bit of alcohol. Just make sure it doesn't drip. Alcohol dissolves most stuff fairly quickly and dries fairly fast.
If they are stuck on good you can use a bit of an acrylic aquarium scrubber pad, but mostly it just smears the poo around and you have to go back with a damp wash cloth to get the rest off.
I like to steal the long Q-tips from the doctors office to reach those difficult places, but I allwasy forget when I am there. When I do remember, my doc laughs at me and says that it isn't stealing when I ask for them.
Cheshire, your scrubbers look nice (I guess, I am a hetero female so I really don't appreciate their beauty as much as I am sure others will)... But I think they aren't abrasive enough to get the dried on bits off. Although the enzymes from the now flowing saliva from the nearest males should help...
... I was going to make a comment about my scrubbers, but nothing good came up.
In my KK's, everything but the spider is contained in a pan at the bottom. I just remove it whole with substrate/plants/wathever accessories, put my baby in a deli cup and wash it like ordinairy dishes!!! Just avoid anything too strong or abrasive or it won't stay clear long!
To remove poo from avic target practice, I usually take a small piece of paper towel and wrap it around the ends of my tweezers, dip it it water, and wipe. Sometimes you have to do it a couple of times, but it usually works.