My ergomonic keyboard has been so helpful in reducing muscle strain.
I usually just use the regular cheap ones at work. 
I used to as well, but the v shape of this keyboard is great.
Does it help with arthritis? 
Maybe.  There is one configuration that requires very little movement of arms and wrists when typing.
Are there certain companies that make ergomonic keyboards?
I can't think of this brand but there must be many as typing , the process of writing, is so prevalent.