Something I've been wanting to do for a long time is taking IR panoramas
This panorama was taken using a filter that blocks out most visible light. The filter, a Cokin A007 89b, is transparent for IR light, and the CCD sensor on my S2 (like most cameras) is IR sensitive. Normally the IR sensitivity is overblown with visible light, but by blocking most visibe light with the filter you get to see the invisible. I have enhanced the colors in photoshop, switching the red and blue channel, among other things.
I have two Sigma 8mm fisheye lenses, an AF and MF version. The MF version has an internal 22.5 mm screw-on UV filter which I replaced by a piece of the Cokin filter. Having both the IR-filtered MF and a 'normal' AF 8mm lens allowed me to quickly change lenses with the camera still mounted. Here's a comparison panorama of IR and visual light:
Using a pair of 'IR goggles' you can see that vegetation virtually 'lights up'. Note how in the minute or so it took me to switch lenses and guestimating a good exposure on the IR pano the clouds and shadows moved considerably, and the duck swam on...