Yellow Lab Tools : Online test to help speeding up heavy web pages
repl.it : Powerful and simple online compiler, IDE, interpreter, and REPL. Code, compile, and run code in 30+ programming languages. including JavaScript, Pytho...
Roam Research : A note-taking tool
for networked thought.
As easy to use as a document. As powerful as a graph database.
Roam helps you organize your research for the...
WebPagetest : Run a free website speed test from multiple locations around the globe using real browsers (IE and Chrome) and at real consumer connection speeds.
Bloody Vikings! : Firefox addon to simplify the use of temporary e-mail addresses in order to protect your real address from spam.
Free online service that allows you to test your emails for Spam, Malformed Content and Mail Server Configuration problems