I feel for you, buddy. Look on the positives; all the good times.
And as hard as it is for you to do, take comfort in being able to say goodbye. I lost my pet rabbit a few years ago; he died quite suddenly. I didn't get to say goodbye.
One thing I found that really helped me with closure, was getting him cremated. There is only one Pet Cremation service in the yellow pages. It was the same as any other meber of the family; there was a little pet funeral home, and myself and a couple of friends had our own little service for him before we put him into the cremation chamber. I got to pick out an urn for him. The person we dealt with was extremely professional.
It cost about $100 5 years ago, and my little buddy was worth it.
On a happier note, I just got a new rabbit a couple of months ago. This new one is nothing like my old one; she's taken up a different place in my heart. Isn't it funny how these little creatures can just sneak into your life like that?