Nice simple style!
Since I don't do too many B/W or grayscale maps, I thought I'd do a quickee island map. I wouldn't call this a "five minute map" more like "fifteen minutes", but I did it for that purpose. There's a G+ community dedicated to challenging cartographers by creating 5 minute maps. I spent 3 minutes drawing the sketch of the isle in pencil, then scanned into Xara Designer Pro 9, spent 10 minutes drawing the shapes of the island, lake, forests, mountains and hills with a freehand drawing tool, also applied rounded bevels on all except the 'mountains' which have flat bevels, light gray/dark gray fractal cloud color mixes, and halo shadow. Then I spent 2 minutes labeling, so as stated, 15 minutes in total... not bad for a quickee map!