We travel with Skibladner fra Gjøvik to Hamar and back. It was lovely to sit on deck in the sun. The kiosk offers tea, coffee, waffles and other snacks. It's a bit expensive, but not more so than other tourist attractions in Norway.
The only negative on this short cruise was the lack of good seating. Since I suffer from...
Just go and enjoy the Cruice on Mjøsa - Norway's biggest and perhaps deepest lake.
Even if it is not obligatory you may want to enjoy dinner:
Salmon, white wine and Strawberries.
It is a very beautiful ship ride - unlike most you have been aboard on...