fxDreema has been online since November 2011
fxDreema uses graphical blocks to build a strategy. Each block has input parameters to change its behaviour
The output product of fxDreema is a file with one of the following extensions - .mq4, .ex4, .mq5 or .ex5
Compatible with MetaTrader 4 and MetaTrader 5
No, it cannot be used to build custom indicators (... for now)
It can be used for free. It stops exporting files when certain number of connections between blocks is reached
It's a Web application, but it's also available as a Windows program and in this case it can work offline
Support - by now, almost all questions got an answer. You can ask something on e-mail or in the Forum (preferable, because the information stays there and other people can use it)

Work with events like - Init, Timer, Tick, Trade, Chart or Deinit
Trailing Stop - you can also trail take-profit, pending orders or group of trades (in MT4)
Global Constants (inputs of the project) and Variables can be used
Break Even
Money managements - Risk %, Fibonacci, fully customizable Martingale, Custom sequence and more...
Check dynamic values easily (from indicators, for example)
Draw and control graphical objects on the main chart window or in a subwindow - arrows, lines, text, fibonacci and others
Send messages to e-mail, website or smartphone
Write data to file
Terminal Variables
Custom blocks can be created and used within projects
Cut, Copy, Paste
History of actions, so you can undo few actions at any time
No need to save a project, just mark the current point in the actions History and it will not be deleted
A copy of the project is stored in the source code files that you export
Source code files (built with fxDreema) can be imported back into fxDreema, which creates a new project

fxDreema works best with Chrome and there is a plugin for easy downloads for Chrome as well. Firefox and Opera are also ok, only God knows about Internet Explorer...
Almost all javaScript code for the browser is manually written. The connections between blocks are SVG (vector) elements
Cookies are used to store session information and localStorage is used to store JavaScript scripts and (not yet) HTML templates
The output code that the builder creates is hard to read and not so fast, but this is always the sacrifice when we make coding easy
nodeBB is used for the forum and also to manage user accounts
fxDreema is hosted on a VPS by Vultr