I've been around the block in corporate. Here's a guidebook (sorry I can't spend more than 15 minutes on this)

1: Get insurance for your product. It will run really cheap for something low-risk like this. (Our firm pays less than 10 grand a year for General Liability, All-risk, and Professional Liability up to 10MM, which is more than good enough for nearly every company out there.)

2: Like Patrick said, the second you throw "HIPAA" compliance up there you have the ability to charge 10 (IME, more realistically, 25x -- but your expenditures increase as a result of that (incurred labor costs of additional support, etc)). At your 20 dollar price-point, you're undervaluing yourself by literally 3 or 4 orders of magnitude. Find an industry (say, that dude who mentioned oil, find out what regulatory institutions dominate), get vendor certified and insured and you're looking at Oracle-esque money + 30% maintenance fees per year + support fees + modification fees.

Corporate sales is all about the steak and strippers (and nepotism) but it's wildly lucrative, even now when oil is trading at like 40/bbl due to SA flooding the hell out of the market. To put it in perspective, Parker hydraulic gear commands a 3 or 4x premium over other brands of nearly-comparable quality. It's a lot like medicine or finance, huge markups but huge barriers to entry re: regulatory certs/risks. I wouldn't sell a site license for the product itself (per actual site, not per corporation, that midtown Manhattan office is billed separately from the LA office) for less than low 6 figures. (Sales cycles are long and expensive, your net on that will probably be 30%, which is why Oracle is always pushing for you to go buy that RAC license, it's only 30% more!)

3: Along the veins of having industry compliance, obviously, offer support. Lets say you want to target the mid-market, Bob the engineer won't be able to do buy the software until his manager sees a support contract available. You're basically not going to maximize revenue targetting this demographic. Supports a must though. (Joel Spolsky factioned software sales off into the "under 1k, petty cash" and "above 100k, gotta take it to the board". Supports a must for either one, at 400 a seat or 400/k/year/seat) I'd target niche oil + board approval market with a relatively long sales cycle (especially if that other HN'er who mentioned oil can get you in for a round of golf with the CIO and give him the 30% rip or whatever's standard now in enterprise sales).

4: Just a note, I take things apart for fun and your product isn't well protected. I'm sure you know that since you left little fun notes around your code base (ps. I do snoop around, and I like you also! haha).

Just another why targeting the "Oracle" demographic (where they literally give copies away with no license keys or anything to everyone on their website), and corporations comply with the fee policies because it's wiser to pay the fees now than have the BSA audit come in and have a 5x fine imposed.

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I made a really long post about here[1] re: medical hardware (another tightly regulated industry with high margins and a sales team that makes or breaks) -- the relevant information is in the last few paragraphs.

There are also .NET licensing components if you make the (imo unwise) decision of targeting the mid-market, which uses USB keys + a network server to limit your trial functionality, but as I'm sure you know, the second those bits hit the hard-disk, someone like me is going to take Olly to it and have it smashed into pieces within a few hours to a few days. Those keys just keep the honest honest (i.e. a company might forget that their trial ran out, or the note to authorize the purchase didn't make it down to their AR/AP dept, etc).

[1] https://news.ycombinator.com/item?id=11543670