Noisebridge has made some efforts to make its space accessible for people with disabilites. Here's some notes on accessibility.
For wheelchair users, it is a fairly comfortable space once you're inside. The front door and elevator may be impossible or quite difficult if you have limited upper mobility. Anyone at Noisebridge will generally be very helpful at running the elevator for you.
Noisebridge's main entrance has a buzzer button which for some wheelchair users would not be accessible. The front door buzzer is sometimes blocked by the supermarket's fruit stands, but they have been asked to stop doing this, and can be told to immediately remove the obstruction if you feel inclined to do so (on behalf of the tenants of 2169 Mission). There are many computerized workarounds to activate the electric door latch. See Getting Here and Access Control for more info.
Once the door latch is "buzzed" either by the button inside Noisebridge or by someone clicking the web-link to do so, the door can be pushed inward by hand or by power-chair, and it will automatically close and latch when released. If you want assistance when leaving, anyone at the space will accompany you to the door and help you out.
The elevator is touchy and doesn't always work unless someone goes up to it by the stairs, closes all the elevator doors firmly, and brings the elevator down. There's a buzzer next to the call button so you can let the people upstairs know this needs to happen, if you can't go up the stairs yourself. When people upstairs hear that buzzer, someone will remind everyone that the sound means the elevator needs to be brought to the first floor immediately. If this does not happen within 45 seconds, please press the button again until the elevator starts coming down.
The elevator doors are heavy and hard to manage, and are not automatically operated. Both the outer door and the inner gate must be moved when getting in and out.
The elevator doesn't always line up perfectly with the floor, so a person using a powerchair could have difficulty getting in or out of the elevator. If that were to happen, the elevator would have to be taken to a different floor and brought back again to the desired floor. This has never been known to be a problem.
 Paths in the space
There has clearly been ongoing effort to keep paths wide enough for wheelchair users. The classrooms have wide entrances and there are clear paths to their tables.
Clutter on the floor in front of member shelves, or in corridors to the bathroom, can be a problem. The server room is very small and the tea room, a small loft with a ladder, is not accessible for wheelchair users.
Keeping clear corridors is an ongoing project. Not every area has wide enough paths for everyone, but in general the furniture is hackable. So if Noisebridge had users who had particular mobility issues and wanted to work in an area that isn't accessible in some way, it is probably fixable.
 Work surfaces
There are many low tables and desks in the space. Some areas, like the kitchen counters and the power-charging laptop area, have high surfaces and so are less accessible. I don't think that means anything needs changing unless a person would like it changed.
Many people at Noisebridge worked on the accessible bathroom. It is big enough to get many power chairs inside and turn around. It is certainly big enough for most manual wheelchairs. There is a second bathroom with a door that isn't very wide, not as accessible as the new bathroom. There are no rails or grab bars in either bathroom. They could both use grab bars. It is important to keep the larger bathroom free of clutter, make sure trash bins or supplies would not block a person in a wheelchair from turning around or being able to open and shut the door.
If you need access stuff fixed at Noisebridge or would like help, definitely talk with people there or speak up on the Noisebridge-discuss mailing list. Tables can be lowered, paths cleared, machinery adapted, stuff hacked!
If you want to be helpful in general, keeping floors clear and furniture widely spaced so that there are wide paths in the space is very useful for people using wheelchairs, canes, or crutches.
Many people with disabilities enjoy NOT to be asked lots of questions about medical history, diagnosis, prognosis, and so on. Why do you need to know "what happened" or "what's wrong" or "whether it's degenerative" so bad before any other conversation? You really don't, so MYOB. There are more interesting things to talk about. Your burning curiosity may be assuaged by getting to know someone for a while, or you know, googling.