Going to a football match in the Czech Republic is a great experience. A wonderful atmosphere with fans from both teams mixing and enjoying a pre-match beer.
Liberec has it's own impressive stadium cut out of the rocks, but if you are in town when Liberec play local rivals Jablonec in Jablonec it is well worth the short journey to see the event.
The Jablonec stadium is situated high up in the town and with bars under all the stands offers very good pre-match entertainment. Enjoy a cold beer and a hot sausage while chatting with the very friendly fans from both sides.
Enter the stadium and marvel at the view, especially if you get the as the sun goes down.
Hopefully Liberec will win a great game to cap off a great evening/afternoon out.
I skied Mt. Jested in the early 1990s and was curious what has changed since then. To be honest - I was a bit disappointed to see that they still run these old ski-lifts. The cable car runs every 30 minutes (with a break from 12 - 13 h) and is not really an alternative. As I read in a German journal they plan to invest a lot of money, though.
The snow quality seemed quite good in late March, the pistes were well groomed.
Apres ski is very limited. The main reason to go are the surprisingly challenging runs and cheap ticket/skipass prices (see their website).
Cross-country tracks are available too. I saw announcements that they will host the Nordic Ski World Championships in 2009. Still some work to do ...
Equipment: Better bring your own. Ski rentals are available, but I did not trust the equipment I saw.
Liberec is sourrounded by Jested Mountain and Izera Mountains where you can ski and snowboarding for the whole wintertime. There's even a ski jumping place.
Don't forget to drink some hot grog after winter crazyness.