Experiment! With that amount of traffic you shouldn't have to wait long to see what works and what doesn't.
just put a site up http://urlsnip.com what do you guys think? its running adbrite and soon adsense edit: http://siteanalytics.compete.com/urlsnip.com/?metric=uv used to get some decent traffic
You could sell some Advertising space on your website here at DigitalPoint, when you can post in the DP Marketplace Forums! You may be able to sell your space for quite a bit as you are getting so many visits. You could also add Google Adsense advertisements, like others have suggested above! To be honest, you are really lucky and getting quite a lot of clicks compared to the work other sites need to do to get that sort of traffic. I am jealous, but at the same time happy for you ! Best of Luck buddy!