It would be really cool if this would have a rule-system programmable by user. Something like - "if I'm next to a good [type] restaurant show a card", "When I enter my flat, show me [last messages, friends updates, ..., n] etc. On{x} (www.onx.ms) seems to be doing it in a pretty interesting way. I'm pretty sure that merging those two ideas would create a very handy product.