>>2
Very well disguised, almost clicked!
>>1
What's there to try? Anyone with good knowledge of their platform's executable format's and a good grasp of the platform's assembly language can code one, but coding virii these days is pointless since even if wanted to create a harmless one, you'd end up having to modify files, which in turn would make some executable's self-checks(checksum/hash) fail, which means you shouldn't code such these nowadays as it's just annoying, instead just read some sources of already made virus from some ezines like 29A, however if you want to invent some new code morphing techniques, then you might be pleased to find out that such skills are sometimes seeked on the DRM/software protection market, which is nothing more than the modern evolution of `virii'-writing - the main difference being that instead of infecting random executables, people pay you to 'infect' one executable, and the payloads represent some restrictions which make the software not work in some specified cases.