Emacs major mode, IDEs, tools?

[Marc Ernst Eddy van Woerkom]

Hello,

I started work on an already existing large Erlang
project and wonder what tools are there around that
might help me to grasp the existing code.

Is there an Emacs mode, syntax highlighting would
be a help already?

Is there any sophisticated graphical IDE, perhaps
an Eclipse extension that is worth trying?

The OOP world uses graphical modelers/code generators/
code reengeering tools like Together, ArgoUML,
Fujaba.. has anything similiar developed in the
world of Erlang?
If not why? Does it make less sense or has simply
noone done the work so far?

Regards,
Marc