The idea here is that you map out your Foursquare checkins, send them to Meshu, and they'll make you a piece of jewelry of the map. You can choose between a pendant, earrings, or cufflinks. Price is actually pretty reasonable, running anywhere from $75.00 US to $150.00 US depending on what material you choose. If your particular Foursquare checkins are boring, they also have a gallery you can choose from of premade pieces. Or, you can map out places you want to go such as national parks or other major landmarks.
Really, that's all there is to it. You can either log in using your actual Foursquare account, or you can map a pattern using their tools, or you can shop from the gallery. If you're into that kind of thing, this might be a neat anniversary gift, where you could choose to map the place you met, where you had your first date, your wedding location, hospitals where the kids were born, etc. Really, your imagination is the only limit as to what your particular piece of jewelry can represent. I should note here that this is not actually an officially-sanctioned Foursquare item.
I think I've convinced myself this is actually kind of neat more than silly. Sometimes that happens.