Seeing all these GPS devices everywhere these days, I assume it's fairly easy to acquire the lat/long values of your current location. I was curious if anyone here has worked with, or has any idea on how to get them. On an old laptop I have I thought it'd be fun to feed the lat/long values into it and read them through USB (or anything) then play around with them in a program I'd like to make.
I would recommend consulting Google (http://www.google.com/search?q=nmea+gps&rls=com.microsoft:en-us&ie=UTF-8&oe=UTF-8&startIndex=&startPage=1) on the subject; there's a lot of information out there. Most consumer GPS devices either connect to a serial port, or use a powered USB-to-serial converter and show up as a serial port on the computer they are connected to.
The above mentioned Google query should get you started on how to process the data as represented by most GPS devices.
I have done some work with GPS (in embedded devices); if all you are interested in is getting the latitude and longitude from the unit, all you need to do is wait for and parse the NMEA GGA sentence (http://www.gpsinformation.org/dale/nmea.htm#GGA).
If you want to do more advanced things, you will need to switch into SiRF mode, which is a binary protocol.
The following may or may not be helpful:
C# Code to compute/validate a NMEA checksum (http://reznor.homelinux.net/~ledbettj/misc/nmeachecksum.cs)
SiRF Protocol Reference (http://reznor.homelinux.net/~ledbettj/misc/SiRF_Binary_Protocol.pdf)
NMEA Reference Manual (http://www.ekf.de/c/cgps/cg2/inf/nmea_reference_manual.pdf)