I tried a lot of different map editors for PnP games but none of them fit a "modern theme" like shadowrun. But now I've found an online planing software on CAD basis where you work with drag and drop system. You can also render the whole thing in 3D and make screenshots in different solutions.
I think a lot of GM's will love this tool when they plan custom campaign and want to design a plan of a building!
Best of all it's free !!
Homestyler
Floorplanner allows any sized Grid, vector shapes that are resizeable, various drawing tools and printing the map over multiple A4 pages or saving it as a huge JPG
Floorplanner
Sweet Home 3d
Envisioneer Express
Furnish Pro
Roomeon 3D planer (German)
My Virtual Home (requires Signup)
Room Arranger
Smart Draw
My Deco
Couldn't find more than that

Hope you guys enjoy it!
If you know more software like this one then post it please, I can always use a good alternative