Is that a joke?
1. Spawn some threads (Python uses native threading) 2. Connect to and load some URLs (This isn't going to be slow anywhere.) 3. Run some regular expressions (Python's regexp engine is all C) 4. Write to the disk. (Python uses the standard system libraries for this)
It wouldn't be as fast, but it might be surprisingly close. There would be fewer lines of code to boot.
The problem would be the GIL (Global Interpreter Lock). You couldn't actually have more than 1 thread running at a time. It sounds like the man only has 1 processor, so that wouldn't be the end of the world, but if he has more, you can just swap in the process module for the threading module. Of course, then you might have some RAM issues.
Twisted is one way, but Python ships with asynchronous libraries http://docs.python.org/lib/module-asyncore.html.
Not actually true; socket calls release the GIL when they're not active, as do many of python's C libraries. Especially the better-written standard ones.
The GIL is not as big of a problem as most people see it, it only interferes with CPU bound, highly parallelizable tasks.
Switching from a scripting language to C doesn't mean an automatic huge speed boost. It depends where your time is being spent.
I wonder what the result would be if you did everything you describe, but wrote the code that's now in C, in Python instead. I suspect the speed would be very similar. (I like C, for what it's worth.)