LightScribe just issued an update for their technology that burns images onto the top of your CDs. The update significantly raised the resolution and quality of the images burned onto the discs. However, you're still stuck with the limited gradient of colors. If you're looking for something a bit more colorful, check out this DiscPainter from Dymo.
Dymo is famous for making labels. If fact, most label makers I see are Dymo brand. Apparently they've grown tired of just making boring labels for files and such. They have just introduced their DiscPainter that will provide you with colorful discs without messing with crazy CD labels.
The DiscPainter prints directly onto the disc, so there's not much hassle. It can finish a disc at a resolution of 600dpi in about 1 minute, if you double the resolution it'll take about 3 minutes. Cartridges will last around 100 prints and will set you back $30. The unit itself will cost $279 and will hit shelves next month.
DiscPainter: You Know, For Painting Discs [via crunchgear]