Actually, Qt has gotten a lot better, and does work on Windows  and  
OS X and linux with claimed native look and feel.
Your mileage may vary and licensing is not free.
On Mar 10, 2007, at 12:37 PM, Sharon Phillips wrote:

>
> On 10/03/2007, at 1:22 PM, Yannick Grams wrote:
>
>> FXRuby looks very interesting: any chance of there being an FXRuby  
>> book?
>
> There's a qtRuby book available (PDF, for US$8.50)
> http://www.pragmaticprogrammer.com/titles/ctrubyqt/
>
> Is anyone able to give a quick rundown on which of these toolkits  
> will work on both Windows and OS X?
> It's not that clear from a number of the sites which platforms they  
> will work on. Some (like qt) seem Linux only. I don't use Linux  
> <ducks> but a mix os Win and OS X.
>
> Cheers,
> Dave
>
>
>