We recently discussed more ideas on sharing alarm clock settings and sharing of the interaction with the alarm clock. Conceptually we have created a design some years back: the networked alarm clock that we published at the 3AD conference . 2008 there was a interesting paper at CSCW that look in more detail what such designs can enable for group communication .
As many people (and I heard that the most used function on a phone is the alarm clock) use their phone as their alarm clock it could be the right time to put some of these idea into reality...
 Schmidt, A. 2006. Network alarm clock (The 3AD International Design Competition). Personal Ubiquitous Comput. 10, 2-3 (Jan. 2006), 191-192. DOI= http://dx.doi.org/10.1007/s00779-005-0022-y
 Kim, S., Kientz, J. A., Patel, S. N., and Abowd, G. D. 2008. Are you sleeping?: sharing portrayed sleeping status within a social network. In Proceedings of the 2008 ACM Conference on Computer Supported Cooperative Work (San Diego, CA, USA, November 08 - 12, 2008). CSCW '08. ACM, New York, NY, 619-628. DOI= http://doi.acm.org/10.1145/1460563.1460660