As much as we are fond of it, urlgrabber may not be for everyone. There are several options out there for fetching files, each with their strengths and weaknesses. If you're writing a python program, there seem to be three major options: urllib2, urlgrabber, or pycURL. Here, we discuss the various tradeoffs of these tools, and the types of programs that might be best served by each:
urllib2 is a pure-python module that comes with the python distribution. It's extremely well-designed and flexible. It is, however, pretty basic. urlgrabber is actually based on urllib2.
urllib2 might be a good match for your application if you only need very basic url access or (at the other extreme) you need to do some very crazy protocol-level stuff. Because it is pure python, you're not likely to be limited by some bug or quirk in the implementation, because you can always just sublass around it if you need to.
urlgrabber is also pure python, with all the associated good and bad that it brings. urlgrabber offers many features over urllib2, but with little of the risk of pycURL; because urlgrabber is pure python and actually based on urllib2, you retain all of urllib2's flexibility and power, but with a much more friendly and featureful interface.
urlgrabber may be a good choice if you need some fancy features but want to retain the flexibility of pure python.
pycURL is a python interface to libcurl, which is a great C library. It supports many crazy features and is very fast.
If maximum speed or exotic features (like gopher) are essential and you're sure you won't need to make fine adjustments, then pycURL may be the way to go.