I'm not trying to go off topic, but as for surface GPS, my dive log app on my phone actually does that. I use MacDive, and the iPhone app version has a location tracker. You just start it before you get kitted up and toss the phone in your dry bag, then when you sit back down after the dive, you select the appropriate spot on the map, name it and save it. Then when you import your dives from the computer (a Teric in my case), it will offer to assign the location to the dive based on the date & time similarity. So having the GPS in the Teric would be nice for sure, but there are some other ways to capture your surface location without it built-in.
EDIT: adding
a link to the docs about the tracking feature.