A program to prefetch tiles for offline use in Gmap.Net
GMAP.NET is an open source map control, you can use multiple map sources based on WEB services: Google map, Microsoft BING map ...
(mostly copied from Gmap NET Demo source)
https://github.com/radioman/greatmaps/tree/master/Demo.WindowsPresentation
The Files are stored in C:\Users[your user name]\AppData\Local\GMap.NET\TileDBv5\en
Once you've successfully prefetched the tiles, you can export the *.gmdb files to portable media (such as Flashdisk) and in the offline pc, it should use it by importing *.gmdb files.