Is it possible to type the pound sign (£) on an (American) Kinesis Advantage keyboard?

On the US-International keyboard under Windows, if you have two Alt keys, the right one gets remapped to AltGr. If you don’t, using Ctrl+Alt provides the same functionality - that is, to enter ß, you would use AltGr+s, or Ctrl+Alt+s.

For the pound-sterling sign £, one would type AltGr+Shift+4, or Ctrl+Alt+Shift+4.

Not a Windows person, but knowing that many modern OS’s now accommodate for easier entry of non-common (aka: “International”) characters with (relatively) simple key combinations.

My first suggestion would be to try some of the “usual” alt-character keys (Shift, Alt and Ctrl) mixed with the $ key and see if that produces a £ (pound symbol). Like this first try with the Ctrl key:

Ctrl+$

Or try just the Alt key like this:

Alt+$

Then try adding Shift to the combo like this:

Shift+Ctrl+$

And finally, try adding Alt to the mix like this:

Alt+Shift+Ctrl+$