Wireflow - Create beautiful flowcharts
SmallDevTools - Handy developer tools with a delightful interface
Mind Map by RealtimeBoard - More than your average mind map
LaunchKit - Open Source - A popular suite of developer tools, now 100% open source.
Platforma Flowcharts - Collection of cards for website and app prototyping
Profitable developer tools database - A database of 103+ hand-curated profitable developer tools