If blue is your color, the Blue Gradient theme is wortha look. Multiple navigation options across the top and side allow for a nice amount of flexibility in arranging things on the site. Demo Download
The Red Evo Beep theme is available for both Joomla 1.0 or 1.5 and features a ton of module choices and is available in multiple color schemes. Demo Download: 1.0 — 1.5
Red Evo’s Flexinews theme is one of the more full-featured free themes out there. It also include 5 different color choices (red, green, blue, orange or purple). Demo Download
Designed to mimic Microsoft Office style appearances, the OfficeStyle theme provides a clean, easily customizable business website. Demo (select OfficeStyle on the page) Download
JS Nova is a super simple Joomla template meant for getting a clean CSS driven site up quick and easy. Demo Download
Happiness is a lighthearted, fun Joomla 1.5 template from TemplateJoomla.com with a fixed width tableless layout. Great for use as a personal site. Demo Download
Although definitely more suited for personal sites, Anemone is one of few free Joomla templates to incorporate Flash into the design, with the left side of the template animated. Demo Download
Designed for use with either Joomla 1.5 or 1.0. Demo Download
Nova is a clean, simple template from JoomlaShack that is perfect for a small website. Nova is highly customizable with three primary modules on the page making it flexible for nearly any use. Demo Download