cool ad platform needs a re-design of homepage

emptyspaceads.com needs a new design for its homepage. It's a relatively simple site with limited content. We need something that's simple, clean and professional. We generally prefer a "white based" design (eg, apple's site has a lot of white and light colors).

EmptySpaceAds

EmptySpaceAds is creating a tool to help website owners monetize their empty space (margins) by serving ads.  The ads only show up when the user clicks on an ad.  We have a current design with content up at http://www.emptyspaceads.com, but we're looking for something better.

LOGO: We like the logo, but we don't feel bound to it.  Do not feel that you have to design around the logo or the current colors.  We are open to designs with different logos.

- [Required] obvious link to "sign up now" and "sign in"
- [Required] clearly state the value proposition: Use the empty space of your webpages to serve ads in a non-obtrusive way (that exact text does not need to appear).
- [Required] slogan is "use it, don't lose it"- [Nice to have, but not required] A demo on the homepage (eg, a spots for ads in one or both margins) with some clear indication that the homepage shows the demo.
- [Not needed] The current icons / links to "people who use emptyspaceads" is NOT necessary.
- [Not needed] The demo page, if you put the demo on the homepage
- [Not needed] The current logo.  Feel free to change it if it doesn't fit in with your design.
- [Not needed] The current color scheme.