tjfly,
I haven't found any good android apps yet, but since I'm now the proud owner of a Nexus 1, I've been having a go at writing my own graphical wind computer.
Rather that the usual 'type in the numbers' ones, it allows you to set direction by spinning round the whizz wheel, and setting the speed with a 'trim' wheel.
I've put some screenshots of what I've got so far at
WindComputer
Is this the kind of thing that people would actually want to use if I made it available??