If you authorize the requests, you'll get a boost of the individual user's available requests after you run out of whitelist API requests for your IP (20000 + (users * 150)). Also, make sure you're using the api.twitter.com/1/ URL format, as they're going to be upping the rate limit for users to 1000 "soon" (it was announced at Le Web 1.75 months ago...).<p>Also, that only applies to OAuth, so you should get on that boat soon. They're deprecating basic auth this summer.