I used to love to beat the take-Australia-first guys – like my uncle, who swore by it – by taking North America: 3 borders, 9 territories and 5 bonus. If you got lucky, you could take NA after 3 or 4 turns, before the Australian champ had much power to unleash.
I remember one Risk game played with 3 or 4 cousins where we somehow stalemated in a huge north-to-south line through Europe & Africa. There were so many armies on the board we actually built huge walls out of them (this was in the ancient game format where they made the army pieces out of wood – yes, wood!! – most were cubes, and the 5s were these plasmoid shapes). So, we stacked up these walls, like four bricks high and three deep, since nobody wanted to “risk” attacking the masses of defenders. Finally there was one giant apocalyptic dice orgy! What a riot. We were all in a stupor by then.
Anyway, RISK is a cool excuse to shoot dice for a couple of hours, and as many have noted, to trade insults and doublecrosses!!