If you’ve got too many feeds and not enough time, productivity site GearFire suggests that you prioritise your feeds by level of urgency; i.e., time-sensitive.
Even when you are rushed, there are some feeds whose content may only be applicable to a short time-span. For example, my subscription to Woot! And Giveaway of the Day are both daily deals, and therefore need to be read before other feeds. Recognizing what is urgent and what is not can help you work when you need, without constantly thinking of your feeds.
This is a simple task that can save you some reading time; for more information on how to read feeds productively, check out how to get good with Google Reader.