There is a new co-working/art/tech space opening on Dudley Street (round the corner from the Electric Cinema) in November, I got a bit of a preview the other day, it's a building site at the moment but it's already looking good.
I've been asked to do a talk at a co-working space this weekend. Its called www.Speedydesk.com which is based in Stechford. Being from London, I have no idea whether the location works for you however.
Good luck with your search
Just to let you all know, here at Innovation Birmingham Campus, we are offering a free trial week for tech companies to come in and use our co-working space. All you have to do is email me (email@example.com) to arrange when you'd like to come in. Happy to answer any questions as well
Not so much hot desking as conference room hire BUT:
On the wall in the 6th Floor 'rest room' in House of Fraser was an advertisement for a Meeting Room to hire.
I think it was £80 for a 14 person room but please check because that seems very cheap.
Alpha Works is a new Co-Working space in the Alpha Tower, Birmingham. There are private offices as well as Hot-Desk space. Free flow tea & coffee, amazing views, 24/7 access, social drinks monthly and café on site!
Does @paulineroche know? She keeps her list up to date atRnR's 'Cafe & Venues Directory': http://www.rnrorganisation.co.uk/directory/
(I haven't forgotten, Pauline! My last couple of visits into Brum have been on tight timescales.)
I've copied @Gemma_Wall's link into this thread too, so everything is together:
...meeting rooms, super-fast broadband, true community feel! alphaworksb1.co.uk