JAX'ing ontop of proguard is another incredibly quick and easy way to save another few Kb (~5%)
And - if you don't have to pass T-mobiles utterly ridiculous acceptance criteria - you can 7zip/kzip the jar to save another 10-15%.
pack all your asset files to reduce the zips table of contents, another 1-2% saving.
Write your code with size in mind - no hardcoded array allocations - minimal member variables, structure your classes so JAX can eliminate & merge them.
Do agressive color reduction on your images (but leave your images in 8bpp)
Match the images palette to the color model used by the phone you are targeting.
pngout/pngcrush all your image assets to remove any ancillery png chunks
etc etc etc
The list is endless.
w00h000, my 1000th post