Sorry if it wasn’t clear, I was adding this info for context and for anyone who hopefully feels inspired to pick up Wave and make something from it given that it was all open sourced and all. And I figured that in the chain after your comment about it having been useful looking all along was a natural place to add this additional info and link.
This was the first big secret “you’re not allowed to know what this is or talk to anyone about it” project inside Google. They wanted to be left alone and especially to not have to integrate with the mail team. And everyone heard rumors of gigantic bonuses if they hit whatever milestones, which wasn’t a thing for other projects. All this made them isolated within the company, and when the project was an obvious flop, you didn’t see anyone rushing over to help them.
I used it to plan a group beach trip back when it came out. We had a single page shared with everyone going on the trip. The page had live shopping lists, maps, weather forecasts, and other snippets of useful information. Now in 2026 I still can't think of any single technology that provides the same utility. Although to be fair, this might be a case of rosy retrospection.