I'll admit it... I SOMETIMES install software for which I've purchased a single license on MORE THAN ONE COMPUTER!!! SHUDDER!!! (I can only use one computer at a time so, to save me the terrible inconvenience of uninstalling from one computer and reinstalling on another computer, I just install on both and live with my guilty concience).
The problem is for such tools, vendors rarely offer "one user, multiple computer" licensing options... as a shareware vendor... since they can't control or confirm such use, they build into their pricing and activation schemes "let's protect ourselves", rather than "let's make life better for our customers". I look at tools and the often arbitrarily high price for the software, and think "if I could go legit on all my PCs for an extra 5 bucks per seat, I would... but I"m not paying full price, like, $40, per seat for my three computers."
The right solution is... lower the price to a point where piracy just doesn't make sense! Yes! I said it! A lot of downloadable software is overpriced... some of it's only worth $4.95 per seat, and software vendors would do well to offer the software at much more reasonable prices, and consider the reality of multiple computers, one individual, and apply some creative pricing options... and a lot of pirates just pirate software for the sake of the challenge, the glory, the WHATEVER, but don't use the software for practical purposes... like, how many PhotoShop pirates are actually graphic designers that make their living using PhotoShop? a fraction of the pirated copies of PhotoShop are used in production (the legal ramifications are too high)... so did Adobe lose a sale to a legitimate user? If they could NOT pirate photoshop, would they go out and spend the $600? Of course not... they'd find a much less expensive alternative.
The cost of credit card processing is outrageous, which makes micropayments impractical, and that's what's keeping the software industry from getting to better license / revenue models, like a monthly subscription of $1 or something, with all updates included while you pay your monthly subscription... but at least Stardock Central / Object Desktop is a step in the right direction.