Simplest method to run three desktop environments

I hope this question still falls within the remit of the stack-overflow exchange..

I need to run three web applications on three different displays as simply and cheaply as possible. Each display will have a user entering numerical information onto the web app.

The web app is a simple html, css and javascript affair that is very lightweight.

The options I have come up with include:

1) A computer, monitor, mouse and numpad keyboard for each user - expensive.

2) A tablet computer (not resistive android - too hard to use) - also expensive.

3) Desktop virtualisation - can't find a simple solution.

Ca开发者_开发知识库n anyone help me with another solution?

More Info:

The users are accessing a local server over wifi. Also the solution needs to run 8-5 Monday-Friday.

Probably there is a way with to drive three monitors, plug in three keyboards/mice, and run three X servers, and make sure the right keyboard/mouse gets associated with each (might be easiest if you use different brands, so you have something to distinguish USB devices).

Traditionally this would be done with X terminals, an early example of graphical thin clients

But given the configuration challenges in getting any of the "sharing" setups right, its going to be hard to beat the cost of three dirt-cheap/older single-user machines, unless you are deploying many of these setups and can solve the problems once.

Virtualbox is free, crashed on me a lot, but I hear it improved. VMware, I love, worth every penny Microsoft Virtual PC.

If you run any of those on a central computer, depending on the OS's you choose to run in the virtual environment, users within your network could be permitted to logon and check.

Simplest and cheapest answer.