I am watching the Euro 2008 qualifier between the Czech Republic and Slovakia, former comrades (hah!) and now sporting competitors. It strikes me how dissimilar are the sporting results are for these two countries after the dissolution of Czechoslovakia in 1993. Comparing football results, the Czechs have done well in the European Championships (runners up in 1996 and semifinalists in 2004); less well in the World Cup, qualifying only in 2006. Slovakia has no real results in any international football competition.
In ice hockey, the Czechs won the Olympic gold medal in 1998, bronze in 2006, and have 5 world championship gold medals. The Slovakians topped out at 5th place in the Olympics, and have only one WC gold medal, in 2002.
The Czechs have about twice the population, I suppose, and are about 50% bigger, but still — seems like a big disparity.