We have an index, it's just not very big, yet. We had a major setback last month with a bug (for less than 24h, the crawler didn't respect robots.txt) and had to delete it entirely, and have been slowly rebuilding it.
You're correct the commercial use is only not allowed before the AGPL comes into play.
You should be able to click on the "top up" link (top or bottom) and see an option for a captcha ("click to prove you're a human"). If you don't, reach out via email (don't share your account number) and I'll give you a voucher for a couple of days.
I've been thinking of making a "small web" indexer so I'm curious about that. I'm seeing even tiny websites being behind CloudFlare, Anubis etc. these days. (And everyone complaining they're getting hammered by mysterious distributed HTTP traffic!)
You can look for Common Crawl or Open Web Index for dataset sizes and how many URLs those include to get a sense of baseline storage costs, and then 2x that for minimum usability.
It's honestly a bit tough to accept that we got a report of abuse and are still dealing with the aftermath of that after having a single crawler go haywire for a few hours (because we play nice and identify ourselves properly), but these... "mysterious" bots that keep hitting all the servers everywhere thousands of times per day just go on like nothing's happening and "no one"'s to blame.
I’ll give it a shot. Always happy to see some competition in the market. And I love the idea of handing out the source after a year.