NimbleText - NimbleText is a text manipulation and code generation tool available online or as a free download.
Popclip - PopClip appears when you select text with your mouse on your Mac.
WordCounter.net - Count words, sentences, paragraphs etc.
Pantherbar - Pantherbar is a tool that lets you perform instant actions when selecting text.
Heytools - JavaScript tools, AJAX tools and some fully server side tools.
Universal Tip - Programmable tooltip that can be used with every macOS app