Oh of course. You can hardly fit a couple of movies into 1GB, let alone follow a weekly hour-long TV show, keep on top of those Debian updates, and upload every photo and video you take to the net :-)

Seriously, I've only gone over my 1GB/mo allowance on a regular phone once, when I was downloading an Ubuntu CD over it to a laptop, over night.

But that was in the days where phones didn't have 32GB storage themselves, and didn't have (semi) HD video, and you didn't send texts as casually as you do with IMs (due to price), and IMs didn't include video.

Even just the keepalive messages (pings) for each online connection in the IM client may add up to >100MB per month, if you have several accounts with different providers.