EasyRider,
All great suggestions. And, for simply having the ability to open another chart while in a room, say to check what the brother's medication list shows, then many of the workarounds above will do.
You mentioned the tabs on a browser. You must remeber two things. First, it is much different downloading a web page to a browser than pulling two charts from Access. Now with SQL, this may change.
With what you're describing, VM seems to be the best bet. Virtual machines would not only solve the problem for the most part, but you would then have the ability to do testing on things as that is what VMs are for. To play with.
The downside would be cost. You would have to decide if it were worth it to you. If you have eight exam rooms, and you need two other OS in each, then you are looking at 16 more licenses. But, with three or so, it would be doable. As stated above some are free. VMWare even has a free one, although I use their Workstation version which costs money. But, it only has one license, so you would have to look at that. Again, you can put multiple OSs on one VM, so you could have 2 XP Pros and a Vista on one VM, but then you would have to pay for them. The other big issue would be RAM, VMs are just that, they are virtual but have their own hardware, etc.
Your computer OS and motherboard can probably only handle 4 GBs of RAM which equates to 3.2 MBs of RAM. So, if you have two other ACs open and you give them a GB, then you have only a GB of RAM on your "real" machine. Not too big of a problem for XP but a big problem for Vista.
You could download Microsoft Virtual PC and try it out. At first, they can be a bit tricky to set up, but all in all not a big deal.