First of all, have you heard of http://RubyMentor.rubyforge.org?
Check that, it might be of great help to you.
Second, an answer:
Most rubyists are divided between GTK, Qt, Cocoa (if you’re on the
mac), wxWidgets and fltk. There are some other contenders - fox, tk
are notable to be quite usable. Rails is recommended for the kind of
apps that can run in a web browser, and I agree. _why blended Gecko,
Camping and Mongrel in a very beautiful way to creaty Hackety Hack and
I think you could do that to create your own app, too.
There is endless discussion about this in the mailing list. About once
per week there is a discussion of 50+ messages saying exactly the same
things about it (and once in a while a discussion that says really new
and interesting things, actually).
At the moment, I am implementing a totally new user interface system
in Cairo. Now, if what you want is to write small apps that are
totally conservative - i.e. familiar to anyone who has lately used a
GUI - that is not the way to go, but if you’re a hobbyist with a lot
of free time that loves the way vector graphics look and knows a bit
of linear algebra (Linear Algebra is not wha you learn at school -
it’s the side of math that deals with vectors and matrices), that’s
really fun. I can help you bootstrap SDL+Cairo to a place where you
My system, when complete, will not be of assistance to you since it’s
got very little to do with WIMP user interfaces, but implementing
simple WIMP in Cairo should only take a few days (and then the textbox
control would maybe take another few days… or weeks… I don’t know,
I’ve always wondered how people implement those and never thought of a
really efficient way, heh).