[epnk]

I would probably go the highest-level route I could, using tools that I am familiar with (and won't get caught in nasty workarounds due to my unfamiliarity with the platform).

In my case right now, I'd probably put together a web mashup using a container of useful platforms--Like Apache ServiceMix using Camel, ActiveMQ, CXF, etc. to grab services, munge them, and output something useful.

Then again, going super low-level might be fun too. Go to the depths of the OS or a compiler and fix an annoying persistent issue.