Email

Spam
Junk emails.. One or two of these may not bother you. The problem is that as more of these spammers get into the game, and they start to use automatic tools to glean email addresses - the spam rate is going to rise exponentially.

10,000 Emails
Do you remember NCSA's Mosaic for the X Window System ? Yes, Netscape V0.0. It was the 'killer app' that brought the WWW to prominence, way back in '93. I worked for NASA at the time, and we used the WWW as a user interface to astrophysics data. At one point while developing an early version, I encountered a bug that arose under a very specific set of circumstances (don't they all?). I sent in a bug report and waited. And waited.. Since this was holding up development I tried every which way to get a response, finally posting something in a newsgroup - and finally getting an answer. They were doing their best, but had a backlog of 10,000 emails. Yes, 10,000!

I suspect that this '10,000 emails' syndrome hasn't left us yet, and is probably a fact of life on the still-exploding Internet.