makes me think of twisted's deferreds for asynchronous network programming: request some data over a network, attach a "worker" callback (and an exception handl

makes me think of twisted's deferreds for asynchronous network programming: request some data over a network, attach a "worker" callback (and an exception handling callback), and your application can move forward without waiting for the response. very awesome for things like parsing <n> rss feeds at a time.