I got used to using jkhl when I starting using vi back in the 80s, so I still use it. Don't forgot about w to jump between words, and several other single key shortcuts.
I like it though it's confusing to enter SQL because your cursor has to be exactly on the first line and if not, it's not clear why your typing doesn't appear.
C for text processing, shell scripts for web scraping (wget, lynx, sed, ...). The elegant design of Unix tools still amaze me. I may do a little Classic ASP too.
Right - The site has been running over 3 years now. There wasn't much competition at first but in the last year I've had real competition plus a bunch of copycats, some who actually copied my code and changed the front-end.
No marketing, all traffic came from search engines. I focused on SEO from the start and that helped with the rankings. I also made sure my site was more functional than the competition. 100% client-side code.
I created http://convertcsv.com and make about $750 a month off google ads. I also have one affiliate link but it isn't producing much. I spend a few hours a week answering emails, and another 2-10 hours a month working on enhancements. As a developer I work with data a lot, and noticed the lack of tools for converting delimited data - so I created my own tools online.
My sites use local storage and I inform the user - consider the possibility someone is using a public computer and you've stored locally what they though was private.
I'd be willing to sell tournamentmaps.com - displays tennis tournament information on a google map. I created this when my kids played but they are older now. Data is scraped yearly from the source and map links to source web site. PHP/MySql
Most comments on the site are thanking me for the site or asking for specific enhancements. So support time consists of reading comments/emails and adding enhancements and/or an occasional bug fix.
http://convertcsv.com - In 2015, I averaged $650/month by using google ads.The site converts delimited (CSV,TSV,...) data to and from different formats (JSON,SQL,HTML,..). It was written in HTML/Javascript and I average about 4 hours a month supporting it.
ConvertCsv.com (http://convertcsv.com) brings me in $600-$800 a month just on google ads and one recent affiliate link. The site converts delimited data into different formats. Written completely in HTML and JavaScript. It's been out there for several years and has steadily increased in traffic.