Hi, I'm a Firebird user, and I will sure buy FB 1.0 CD as soon as it's release with the only goal to support "financially" your efforts and work.
I think that this feeling of "support who is giving you real value for free" is getting more and more attention, in part due to the financial crisis or difficult of free software firms.
My suggestion is: include something that your "supporter" can show as a symbol of their contribution! I think a good thing should be the moral right of putting in their programs' about box a special version of "power by firebird" logo, something with "Active firebird supporter" written on the bottom, maybe with a slight different colour, or something like that (you've got the idea).
I think that you will surely include something interesting in the CD that can justify it's buy by itself, but I think that my suggestion can improve things even more... and push FB "evangelisation".
Considering that this will cost you only some bytes and 10 minutes with Photoshop...

Thanks
Marco Menardi
Btw, I've nothing against Borland, they give me Delphi! My only real complain is about it's "open not open" and "weak, poor open version" management of Interbase. Too bad :(