Heya Hunter folk,
I somehow stumbled upon this: http://www.wowhead.com/item=34105#comments
The Quiver of a Thousand Feathers (which can no longer be learned – but whomever had it as a leatherworker still can create the pattern) works as a 20 slot bag AND (supposedly) still shows as a graphic on your character when equipped.
Cool eh?
It is apparently buggy – and there seems no rhyme or reason why it does or doesnt suddenly appear. Also – I have seen screen shots of it on priests! So apparently it may work on non hunters. I have the pattern and just equipped it to test and have not seen it – but have heard that it takes logging in and out or other oddities to get it to show.
Ill report back in when I get home from work. 😉
<edit> Still no luck 'seeing' it. 🙁 I thought I was going to have a new source of income with a cool 'no longer in game' pattern! I am starting to wonder if the 4.3 patch (or earlier) did away with the quiver graphic showing up. 
That would have been so cool