I was a big fan of the Sidekick. I had every model since its introduction until the Sidekick 2008. And I had service activated up until Microsoft screwed the pooch on the service in late 2009, even though I was paying for 3 phones in order to keep it.
It truly was a great device. Not necessarily better than a Blackberry for email, but definitely the best at browsing the Web, until the iPhone and Android devices came out. And it was really the only device that did IM right, even including the current iPhones and Androids, with true always-connected messages and statuses, with an intuitive interface. I’m sure I’d miss it a lot more if IM hadn’t become largely irrelevant to me personally. But I’ll still miss it.