I ride my fixie with my iBook regularly. I had it in my book bag last fall and went down fairly hard. The iBook's display was shifted, but seemed to operate for the most part. It also developed some weird condition where it would lock up every now and then for no good reason. Luckily, I bought laptop insurance last year and I was able to get it repaired without any problems. 0$ deductable. I was happy as I am a poor student and couldn't replace without saving for a few months.
If anyone is interested in the name of the company that I used for laptop insurance, let me know and I'll send the name to you. They were very quick and polite and gave 0 hassle. Had my repaired iBook back within 10 days. I highly recommend them.