I've been working on an HTML5 game engine / editor called Booty5 for the last 6 months or so that I use for my own personal projects. I've made it free to the development community to enable everyone to benefit from it.

Heres a basic feature list:

• Create and organise game levels / maps and app layouts into scenes and actors (smart sprites)
• Create and preview complex Flash style timeline based animations of entire scenes and their game objects
• Complete game and app creators integrated development environment (IDE)
• Export in multi-resolution friendly format, allowing exported data to be used on any sized display
• Assisted layout editing, including tools to enable easy layout / layout management, bookmarking, edge / vertex snapping, directional cloning and so on
• Full drag and drop support, drop entire folders of resources onto the editor and it automatically sorts them all for you
• Support for import of SVG, Texture Packer, audio and other formats
• Support for physics including materials, shapes, fixtures, joints and the ability to test physics
• Support for Javascript and other language editing, includes syntax highlighting, code folding and search / replace
• Create and edit shapes, trace bitmaps to optimised shapes and split concave polygons to convex
• Create and edit gradients then assign to game objects
• Interactive play mode that launches the game from the editor
• Create complete working / runnable projects right in the editor, no back-end services required
• Support for bitmap animation
• Support for user properties
• Exports JSON so output can be used by any game engine that can read JSON
• Export to Marmalade Web and CocoonJS, also tested with the Intel XDK

And a quick screen shot:

The game engine is open source and available on Github. Demos are available on the Booty5 demos page.

looks awsome!

New update available 1.8.9b, main change is a complete restructure of the engine code and support for action lists. Complete list of changes include:

• Code restructured
• All classes moved into the b5 namespace
• TheApp class renamed to App
• window.app replaced with b5.app
• Added new property to App called canvas_fill_window which when set to false will prevent the canvas from being resized to fit window
• Added support for sequential and concurrent actions to app, actors and scenes via ActionsListManager and ActionsList classes
• Large collection of pre-defined actions added:
  • A_ChangeActions
  • A_CreateExplosion
  • A_CreatePlume
  • A_ChangeTimeline
  • A_AttractX
  • A_AttractY
  • A_Attract
  • A_Sound
  • A_CamStopMove
  • A_CamGravity
  • A_CamMove
  • A_CamMoveTo
  • A_CamFollow
  • A_CamFollowPath
  • A_CamFollowPathVel
  • A_CamLimitMove
  • A_Wait
  • A_SetProps
  • A_AddProps
  • A_TweenProps
  • A_Call
  • A_Create
  • A_Destroy
  • A_FocusScene
  • A_StopMove
  • A_Gravity
  • A_Move
  • A_MoveTo
  • A_MoveWithSpeed
  • A_Follow
  • A_LookAt
  • A_FollowPath
  • A_FollowPathVel
  • A_LimitMove
  • A_SetLinearVelocity
  • A_SetAngularVelocity
  • A_ApplyForce
  • A_ApplyImpulse
  • A_ApplyTorque
• Actor.setPositionPhysics() deprecated, use setPosition instead
• Actor.setRotationPhysics deprecated, use setRotation instead
• Moved getResFromType() out of App and Scene classes into common Utils class
• Added new Utils.findObjectFromPath() and Utils.resolveObject() which can be used to find actors, scenes, action lists and timelines from a path such as gamescene.actor1.timeline1
• Added new Utils.findResourceFromPath() and Utils.resolveResource() which can be used to find resources from a path such as gamescene.sound1
• Added new _atlas, _bitmap, _clip_shape properties to Actor that can use resource paths as well as instances of resources
• Added new _clip_shape property to Scene that can use resource paths as well as instances of resources
• Added new _focus_scene and _focus_scene2 properties to App that can use resource paths as well as instances of resources
• Added vx_damping and vy_damping to scene camera
• Updated Xoml.js to load new actions lists from Booty5 editor exported JSON format
• generateExplosion, generatePlume and generateRain now also accept string version of type
• Logic and rendering decoupled. Logic (app.mainLogic) now ran on timer at default 60 fps whilst and rendering (app.mainDraw) at max frame rate
• New Actions example added
• Fix: Animation.Update() locks up when only a single key frame is specified
• Fix: “none” rescaling method was not working correctly
• Fix: Box2D forces applied in Actor OnTick were not being applied

Booty5 game maker editor changes v1.8.9b include:

• Added new property to project section called Fill Window which when set to false will prevent the canvas from being resized to fit browser window. Setting to false is useful if you have a canvas that fits in vertically with other page content as no borders will be shown.
• Updated events editor
• IsPath added to Shape properties, which can be used to mark shapes to be used as paths
• Added actions system and Action List editor to Actors and Scenes
• Project property Frame Rate now exported
• Fix: Proportional origins were not working
• Fix: “Wait for resources” project option not saving correctly
• Fix: Attempting to export a project that has a brush that points to an image that is not present on disk crashes

The Booty5 free ebook is now available http://booty5.com/booty5-free-html-game-maker-e-book-manual/