I assume that most people who work in a cubicle farm have gone to a movie in the last 12 months. I would assume that those people do not enjoy having their movie interrupted with an annoying ringtone during the dialog that they would like to hear. It's distracting, and rude.
Why is the office any different? Especially as a software developer, I guard my noise level very much. Is it too much to ask that we honor each other and set our cell-phones to 'silent' during the day? Is it truly necessary to have your sci-fi-esqe ring tone at full volume, and let it ring for 5 seconds?
I would encourage everyone to put up a sign in their cubicle area. Microsoft has a few in their Office downloads area to get you started. Go xerox a dozen and hang them! http://office.microsoft.com/en-us/results.aspx?qu=cell+phone+flyer
Spread the word! Lets make cubicles everywhere a quieter place to work.