I searched for a way to schedule tweets for a future time like I schedule blog posts. Three different services showed up at the top of my search, Tweet Later, FutureTweets and Twuffer. Tweet Later immediately turned me off by how ugly they were. FutureTweets looked the most attractive but then I realized I had to register for its service.
With Twuffer I could simply use my Twitter username and password. It proved pretty easy to use its service which I did to schedule tweets while I was on my cruise vacation last week.