There's lots to do in and around Sapporo. Besides Otaru, which is an enjoyable day trip, the Sapporo City website has a few suggestions for things to do in Sapporo itself:

http://www.welcome.city.sapporo.jp/e...ites/list.html

If you like seafood, visit the fish market in Nijo, southeast of Sapporo Station, for some excellent fresh fish (and just about everything else that lives underwater), though you have to go in the morning and sometimes you just don't want fish for breakfast (I'm about 50/50 on this). I had a sea urchin/salmon roe bowl last time I was there.

The fish market isn't too far from the "Keyaki" ramen shop, which is said to have the best miso ramen in Japan. I can give you directions if you like ramen and want to check it out.

I think it's best to visit Odori-Koen, where all the sculptures are found, at night when everything is illuminated, there are fewer people (it will still be crowded), and things start looking surreal. If the weather gets really bad you can use the Odori-Koen subway station to walk underground for most of the length of the park.

There's a beautiful view from the top of the JR Tower above Sapporo Station. Because Hokkaido doesn't have nearly the smog problem that the big urban centers to the south have, you can often see a long way indeed. It's great to look from the Sea of Japan up near Otaru all the way over to the Pacific Ocean; sometimes you can see snow rolling in from the west and gradually obscuring the view until it's snowing like crazy in downtown.

The TV Tower in Odori-Koen gives you the classic view of the park, but it gets hideously crowded during the snow festival.

I've been up to the Sapporo Olympics ski-jump venue; this isn't a must-see but it is fun to visit if you like winter sports and does provide yet another great view. There could be an event going on while you are there. There is lots of skiing nearby Sapporo as well.

Sapporo Beer's Hokkaido Brewery isn't too far out of town if you love great free beer (I'm a Sapporo junkie).

http://www.sapporobeer.jp/english/guide/hokkaido/

There's also the Sapporo Beer Garden downtown which sells all-you-can-eat Genghis Khan lamb barbecue and all-you-can-drink draft beer.

http://www.sapporobeer.jp/english/guide/sapporo/

And not to appear too fixated on alcohol, but if you visit the bar and club-filled Susukino district, there will probably be a few liquor companies that have set up bars... made of blocks of snow (and hopefully offering free samples).

In midwinter most streets in Sapporo have a few inches of ice and snow on the roads; cars and buses drive by as if it were nothing at all - you'll even notice young ladies courageously wearing high heels in the worst of conditions. Hokkaido in winter is a heck of a place.