UPDATE: This theme does not seem to be free anymore. I updated the title and post to reflect that. Thanks Tyler!
Eveek.com has just released a slick modern theme called BlackPack. Personally I am not fond of the items on the today screen but the look is very impressive. It looked hot on the 8800 I installed it on but it may not jive with the device colors of your 8300. I like the icon choices but the extra glow around the icon is a bit much and makes them hard to see. The menu font is also not one of my favorites but it matches the overall theme. Thanks Eveek!
I really find it confusing why great theme authors such as Eveek and Themes4BB post their themes on a forum. The forum structure leaves no easy way to access them from your BlackBerry to install OTA and no good way to browse through the available themes. I really wish they would come up with a better delivery mechanism or just have a mobile friendly version.