Amazon's official tools for interacting with EC2 are kind of clunky and a pain to deal with. I have to set up a bunch of environment variables, store separate private keys just for EC2, add extra items to my PATH, and so on. They all output tab delimited lines that are hundreds of characters long with no headings, so it's a bit of a pain to interpret them. Their instructions for setting up an SSH keypair give you one that isn't protected by a passphrase, rather than letting you use an existing keypair that you already have. The programs are all just a bit clunky and aren't very good Unix programs.
So, are there any easier to use command line tools for accessing EC2? I know there is ElasticFox, and there is their web based console, which do make the process easier, but I'm wondering if anyone else has written better command line tools for interacting with EC2.
ElasticFox is handy for most tasks. They are occasions though that a command line tool will be better suited. I personally use boto library for python. It is very easy to script all the required operations. You can also use it to upload/download files from S3. In general, I would say that a scripting language like Python or RUby, together with a AWS library, is the best solution.
I personally use Tim Kay's Perl command line tools and haven't used original Java based API for quite some time. Excellent for UNIX environment.
If you use windows, try the tool linked below (part of the O2 Platform) which gives you an easy way to start and stop Amazon EC2 images (and if you need to extend the tool it you can easily add new features (since it just an C# script that is dynamically compiled and executed)