The Google Dashboard is a handy tool for keeping up with what information Google has stored for you in its various different products. One piece of the handy information, though, has taken a while to become available but it's there now: your Android devices. It's unclear if this feature has been around for a while, but either way, it's useful. If you'd like to see which devices are registered with Google, and more interestingly, which apps on those devices have backups stored on Google's servers, you can do so from your dashboard.
Recently, Wolfram Alpha LLC dropped the official WolframAlpha app into the market. It is one of my favorite services and I purchased it ($1.99) as soon as it came out. For those not familiar, this is a clip from the "about" page of WolframAlpha to give you some idea of what this is all about:
Wolfram|Alpha's long-term goal is to make all systematic knowledge immediately computable and accessible to everyone. We aim to collect and curate all objective data; implement every known model, method, and algorithm; and make it possible to compute whatever can be computed about anything.