Go to Options>Reading in the admin panel and change the number of recent posts displayed to 1. Caveat: This will make it so that all of your post listings (all archives, category listings, etc.) will only display one post. I don’t know how to make only the front page display one post. Someone else will have to help you with that.
Anyways, I set my reading option to 1 day.
And then used the Custom Posts Per Page. That allows me to display many posts on the archive pages, BUT its not consistent maybe on one page there’s 5 on the another there’s 6, and so on. This screws up the paging – even though there are no posts in the previous page, it still displays a link to the previous page.