MOBIFY makes desktop sites appear on mobile as if they were designed for a small screen. In just minutes, create a mobile view of your website, improving its compatibility with thousands of devices. MOBIFY provides a high quality, effective mobile strategy while maintaining your brand, domain and site structure.
One of the best web apps out there!
Mobify is a terrific, easy way to create a mobile version of your website. You simply select the page sections you want, customize your selections if necessary, tweak your CSS, and you've got a mobile page. In half a morning, you can have a fully-functional mobile site.
It also has easy-to-set-up custom sub-domain (m.yoursite.com, for example) and mobile device detection scripts (also plugins to some CMS systems--I haven't used that part yet).
There's a free version (with their branding) and two levels of paid versions ($25/mo. and $99/mo.).