I think it would be pretty nice to see a dual monitor version of Aquarium (by far the best screen saver ever written).
It seems like more and more people are setting up dual monitors these days.
I recently purchased a GF4 which has built in dual monitor support and I am currently looking at a second monitor to add to it after successfully setting up a dual display at work (using 2 vid cards). I've found that once you have tried dual monitors for work or play, you will not want to go back to a boring, less productive single display setup.
As for Aquarium having to be written for dual monitors, I don't quite understand why that is needed. With every program I have tried at work, just stretching an application to the second window seems to work just fine.
Here is a link to the best multi-monitor resource site on the web:
http://www.realtimesoft.com/multimon/
Oh, and here are my dream monitors:
http://www.massmultiples.com/
http://www.9xmedia.com/
http://www.panoramtech.com/products/pv230.html
I wish someone could buy one for me at xmas but I doubt anyone will.
Anyway, keep up the great work on Aquarium!
I also wanted to mention that there is a directX 8 SDK for dual monitor screen savers located at the realtimesoft site as well. It's under the month of January news, here's a clip:
Microsoft has included an amazing 3D screen saver in the DirectX SDK for developers, with full multi-monitor support and hardware acceleration on each monitor. Download: Moire.scr (336 KB), requires DirectX 8 or later. If you are developing DirectX applications: the sample is in \direct3d\screensavers\moire, looks like they have an excellent screen saver framework.
The UltraMon SDK and UltraMon Developer Edition have now been updated to Beta 6, the new versions can be downloaded here. If you are a C/C++ developer, you can already use the new monitor control (IUltraMonMonCtl interface), this is the same control used by UltraMon for the wallpaper and mirroring dialogs. Check out the MonCtl sample to get started.