codepad.org is an online compiler/interpreter, and a simple collaboration tool. It's a pastebin that executes code for you. You paste your code, and codepad runs it and gives you a short URL you can use to share it. Paste the URL into chat or email to get help or to show someone how to do something. Or just try things out when you don't have an interpreter handy. It works well on many phones.
IDbin is a free OpenID authentication provider used by Pastebin.ca and the related sites. By creating an account here, you are able to access all of the other related sites, like the Codebin, with a single user account.
No Java, no flash. With Mibbit, chatting online is easy, just choose your nickname and press go! No sign-up is required and you can use it from wherever you are with just a web browser.
specifically designed to help JavaScript and CSS folk test snippets of code, within some context, and debug the code collaboratively.
JS Bin allows you to edit and test JavaScript and HTML (reloading the URL also maintains the state of your code - new tabs doesn't). Once you're happy you can save, and send the URL to a peer for review or help. They can then make further changes saving anew if required.
Save and share. You can save anything - contacts, notes, code snippets, lyrics, to-dos, whishlists, links, etc. And watch for news - we will add new types of knowledge.
