I recently signed up for simyo, a German cell provider. After installing the Nano SIM into my phone, I noticed that the 3G connection to the mobile data network was failing. Got a weird error that said I was not subscribed to a mobile data network. Which was obviously false.
So, I tweeted about it. Expecting a several-day delay in my support query from simyo, I totally resigned to wait on mobile data until they got back to me. But luckily this new 6W family & friends totally came to my rescue. Rafif Yalda, a former Wunderkind, totally came to my rescue in a tweet (which has since been removed).
So if you ever run into a problem with your mobile network, ensure that your APN settings are correct. In this case:
APN: internet.eplus.de username: simyo password: simyo
tip to Rafif Yalda for the tip. This surely saved me many hours of frustration.