Suggestions for good material for a reading at a non-religious wedding?

I am doing the reading at my sister’s wedding and I need some good suggestions. It’s a non-religious ceremony conducted by a reverend. He suggested skipping the reading, since it’s almost always the part of the ceremony where everyone mentally checks out, wanting things to cut ahead to the good part (vows, kiss, etc). I know I usually nod off during the reading myself. My sister wanted to keep it in though—I think it’s mostly because she wants me to participate in the ceremony with her.

Now I’m stuck with the difficult task of trying to come up with some good material for a reading that won’t put everyone to sleep. If it were a best man type speech I would be fine (I’ve got plenty of material/dirt on my sis for that), but readings are very different animals. This brings me to this question and all of your collective wisdom. The ideal reading would be funny (but not inappropriately so), have a deeper message that made people reflect a bit with sincerity, it could be religious (any religion really) but certainly dosent have to be and might be surprising or somehow unexpected in a fun and lighthearted way. I’m hoping for something great because I love my sister so much, and I would feel terrible if I let her down. I think people’s expectations are pretty high of me on this one.

I welcome all of your suggestions. If you have experience doing a reading at a wedding, any tips in that department would be welcome as well. Thanks so much for your help.