I said it would happen, and here it is: a 1TB external hard drive for less than $100. Specifically, Buy.com has the 1-terabyte Cavalry CAXE3701T0 dual-interface drive for $89.99 shipped (after a $50 mail-in rebate). Yowza.
Because it's preformatted with NTFS, it's plug-and-play ready for Windows users. (Mac and Linux folks could easily reformat it, I'm sure.) The drive includes both USB and eSATA interfaces, and even comes with a SATA bridge cable so you can connect it to an internal SATA port (handy for those systems that lack an external one). Why bother? Oh, maybe because SATA transfer speeds are about six times faster than USB 2.0.
This is a new drive, of course, with a one-year warranty. The rebate offer [PDF] expires today, so don't wait too long. This is the first time I've seen a 1TB drive for under $100. (Remember when these babies sold for $400-plus?)