I thought you had to pay for XV for "personal use" as well? I'm not doctrinaire about software having to be free either, as long as it's not ridiculously expensive like Windows Vista.
You don't HAVE to pay for personal use. Here's what it says at http://www.trilon.com/xv/pricing.html
"xv is shareware for personal use only.
"You may use xv for your own amusement, and if you find it nifty, useful, generally cool, or of some value to you, your registration fee would be greatly appreciated. $25 is the standard registration fee, though of course, larger amounts are quite welcome."
That's a pretty low-key beg, and it seems to be up to you to judge whether xv is useful enough or nifty enough to you to be worth $25. Registration is required if you use xv in the course of your work.