iOS: If you incessantly check one or two websites, then loading up Safari each time can get cumbersome. Glimpse lets you put any web page you want right in Notification Center.
Once you pick a page to monitor, you select a small section of the page, then Glimpse refreshes that for you periodically. Pull down the Notification Center, and you get a quick look at what the site's up to. It's not especially handy all the time, but it's great if you're monitoring a specific page for a release or a bit of news.