Weezer frontman Rivers Cuomo has put all the band's demos in an online marketplace for fans to purchase, but he did it as part of a class project. He's been taking a course titled CS50's Web Programming with Python and JavaScript. The demos can be found under the “Market” tab on Cuomo's Mr. Rivers' Neighborhood website.
Cuomo has broken down his demos into periods of his career, including his pre-Weezer solo stuff under the “Alone” title, “The Best of Demos,” which he suggests starting with, and runs through the latest White Album.
The largest set is “The EWBAITE Years,” taken from the period when Weezer recorded Everything Will Be Alright in the End. It clocks in at over 38 hours with 1113 demos.