Basically you start the server on the desktop PC (the server sits quietly in the system tray), then start the client on the (ActiveSync-connected) Pocket PC et voila, you can use your finger on the PDA touchscreen to move faders and push buttons.

Faders and buttons that can be freely assigned to MIDI CC. How sweet.

Theresa has customizable layouts, she's skinnable and can save/load presets. Last but not least, she's freeware (as in free beer) and open source.

So, if you can't afford a sturdy Doepfer, a powerful Mackie or a classy Novation Remote, and you have an old iPAQ or similar laying around, it's time to meet Theresa and rejoice.

Theresa will be of very little use without these fulfilled:
- A Windows PC with the .NET Framework installed.
- A Pocket PC / Windows Mobile PDA with the .NET CF (1.0, later versions should be compatible) installed.
- Activesync to connect them.

Installation:
- Put the contents of the "client" directory somewhere on your Pocket PC.
- Put the contents of the "server" directory somewhere on your desktop PC.
- Start the TheresaServer.exe program on your desktop PC.
- Start the Theresa.exe program on your Pocket PC.
- Open the configure screen, select a MIDI output device.
- Enable the corresponding MIDI input device in your favourite music program.
- Map the parameters, do MIDI learn, tweak, tweak, tweak!

In the "vstmap" directory there are example MIDI mappings for some VST instruments. you can load them in VSTHost, then open the corresponding preset in Theresa.