AWS Cloud9 IDE
AWS Cloud9 IDE is incredibly easy to set up, and is an affordable way to do some work outside of our normal development machine. If you have an AWS account already set up, building a Cloud9 machine just takes about 1 minute, and is immediately available for use. When you're done, the EC2 instance will power down after a short time, meaning you're only charged for the EC2 time, plus the storage space for the persistant disk. This may be significantly less than you'd pay with other subscription cloud IDEs, depending on your situation.
Out of the box you get a bunch of languages/frameworks ready to use, but if you're looking for something like .NET, you have to install it, but that's no problem since you have full access to the underlying machine.