Ask HN - How to find APIs, API directories?

Mashery also has a big list of the APIs they enable: http://dev.mashery.com/apis

And Google's APIs: https://developers.google.com/

I think ProgrammableWeb is pretty comprehensive though.

ProgrammableWeb is my go-to resource too.

There's also: - http://www.mashape.com/ - http://apis.io/ - http://data.gov/

less quality than programmableweb but some APIs only there http://www.webmashup.com/

That's pretty much the best one.