THis is a general question & i do not know where to look for information on this.
I am looking into a project whereby i would like to have 2 people enter data into the same cpu with 2 different keyboards.
for example.
We have 2 people counting money.  the first person counts & the second verifies.
I would like for the first person to enter the amount of the count into a database(MS Access)and i would like the second person (who does not see the amount the first person entered) to enter the amount he/she came up with.  If the amounts agree the system would indicate continue on and the counters would go on to do the next count.  If the 2 amounts do not agree then i would develop a popup for them to do a recount.  

IS such a thing possible?
(2 keyboards on one CPU)

Officework,
    Yes, you can put 2 keyboards on a single machine, but not really simultainously.  In otherwords, there are KVM's (Keyboard Video Mouse) sharing devices that allow you to run multiple machines from a single KVM, and there are "Keyboard" switches that allow you to use multiple keyboards (thought this is somehwhat a backward concept, but does work).  The trick is, you have to rotate an A/B switch to select which keyboard is in use, as PC's only have 1 keyboard "Input" for processing at any given moment.  Hooking two of them up via a Y cable would likely result in damaging your computer, if both typest typed at the same time, or even just plugging it in.
     Personally, I think what you are trying to achieve is best done using other, more rigerous accounting methods than this type of solution.

Best Regards,
Scott

"Everything should be made as simple as possible, and no simpler."

This sounds like a data-entry verification problem.  We used this in verifying data from ticket sales and survey research.  You need a program which records entry from the first operator and then has a second operator verify the entry.  If they do not agree a bell sounds and the amount is required to be entered twice again correctly.  The program we used was DataStar which is very old but investigating some survey research firms for what data verification software they are using may come up with new names.