Could you use this time more profitably? And still set homework?
Perhaps you want a little time to think of the best homework to set and to invent it at the end of the lesson is not the best way to set an appropriate homework.
Perhaps you have homework already mapped out for the whole term. Perhaps not.
Have you thought of emailing homework to all your students? A bit of a pain as you have to keep their email addresses up to date.
What about using Twitter?
Yes, students have to log onto Twitter to receive the homework but that has advantages.
Advantage 1 - You can include links to web pages and other resources in the Tweet.
Advantage 2 - You have to compress the homework to 140 characters. You have to think about that.
Advantage 3 - Students HAVE to seek out the homework. They have to be motivated to do this and we know that intrinsic motivation is better than extrinsic for creative work. See "Drive" by Daniel Pink.
Advantage 4 - You set homework once, and don't have to think about email addresses at all. All students need is a Twitter address to look for the homework. (You know that you can have more than one Twitter address - see, for example, Hootsuite which can manage more than one Twitter name)
For me all of these are good but advantages 3 and 4 are the most attractive.