pouët.net

http://www.xpounded.netfirms.com/jasm/jasm.html

I don't know if the JS code is just meant to be very easy to read, but some of it is on the verge of being ugly code. (When there are builtin functions in JS that could do the same thing better.)

beautifully useless :)

a_lee_n: OTOH this is one is utterly cool as you can run the code.

bigendian x86 assembler, veeeery useful.