Many game engines are going opensource which is good. But as a dabbler some of them are really advanced. And some have some dependencies that make them difficult to use on some OSs. I think Haxe requires ocaml for example.

Here are the ones I know about:
CryEngine
Godot
Unity
Unreal
Haxe


Anyone used any others?

Off the top of my head?

Source
Ogre

Are you asking about the ones with silly dependencies?

Most of them I'd imagine. I love the id-tech engines, and obviously love that Carmack open-sourced them, but they'd be considered a bit dated now. Without knowing much about their technical capabilities, just from eyeballing, I'd say Unreal and CryEngine look the prettiest.

There's also JMonkeyEngine and libGDX, both multiplatform and open source, although built for the Java side of force

JMonkeyEngine is one of those IDE+SDK included, full featured engines.
libGDX on the other hand comes without it's own IDE but it's still a game engine, just lower-level and with fewer features. I've used it with my own graphics engine, to handle sound, files, networking and input in a multiplatform way.

If you're not into Java, some other engines worth mentioning:
Torque - I've heard it's decent for strategy games amongst others
SFML - another low-level engine, but this time primarily for C++, quite popular on GameJams, I've heard. This one is mostly for 2D games, but there's nothing stopping you from making 3D games in it, if you do the OpenGL stuff yourself, or use it for the non-graphics stuff, and use some dedicated graphics engine (Ogre and Irrlicht come to mind).

Then there are 2D engines, such as LÖVE, RenPy, if you're into scripting languages. Just mentioning them, because I've encountered games made in those on more than one occasion.