In my freelance job I often need to wait for responses from various people. Tipical is the case when I send an offer to a client, and I have to wait for a response. It's a critical question, as you can understand, and I usually sign it in my "waiting for" list. But now this list is becoming too long. I have dozens of this stuffs waiting for and this list is too time consuming to manage. How do you manage this? Do you use separate waiting for lists? (for pending offers, for delegated activities etc)?