I am a long time Cloud9 user, altough i have never paid a dime on it (i use their free features) i am a declared fan. Cloud9 is a complete development environment that lives in the cloud, yes, you just start your browser, point an url, sign in and voila, you can start coding in the cloud for free by creating a customized virtual machine for your taste, be it Python, PHP, C++ etc. it even gives the option to create a completely customized VM with whatever you want on it. A great tool indeed, great for proofs of concept, mocks etc. I have tested other online IDEs but Cloud9 stands apart for their large set of features. Well, i just received an email from Cloud9 and guess what, the have acquired by no other than big giant internet monster Amazon and they will be part of the Amazon Web Services stack. Is this good or bad news, i have a feeling (hope i'm wrong) that this is the end (like "The Doors" said) to good old free features and we will have to start to pay.