Thinks to do while in Vancouver
First, map to get you oriented:
The most valuable resource for touring the city and finding things to do is the Tourism Vancouver website, http://www.tourismvancouver.com/. They have a whole section dedicated to things to do. It lists everything from dining to shopping; their information is far more exhaustive and thorough to replicate here, so be sure to check it out for yourself if you are planning to hit the town!
Restaurants
Tourism Vancouver - Dining (though my inclination is to talk to locals for suggestions rather than to rely on a potentially biased website. 
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Locals from the Vancouver area have recommended the following restaurants:
Seafood
- The Stanley Park Fish House. Walking distance from the hotel – about 2km. Somewhat pricey but great location and excellent food. http://www.fishhousestanleypark.com/index.php#
- The Boathouse on English Bay. A great view of the sunset. Probably a bit cheaper than the Fish House. And a slightly shorter walk. http://www.boathouserestaurants.ca/2004/english_bay.htm
- The Cannery. Fairly authentic looking cannery/dockside construction. Right on the water of Burrard Inlet. A bit of a drive or taxi ride. Robust menu. http://www.canneryseafood.com/
- A Kettle of Fish. No views at this place. A bit longer walk – maybe 3km, but a great stroll along English Bay getting there. http://www.akettleoffish.net/
Other
This is Vancouver. Go for the seafood.
Nearby activities (information provided by Paul Zablosky)
The most popular walk is the seawall. You can walk right around and get all all the views, seaside, yacht harbour, totem poles, west coast forest, Lions Gate bridge (you walk under it), the mountains, etc etc. The whole loop back to the hotel is a bit more than 9km, but you can see all sorts of ways of shortening it by cutting back on park trails. (Make sure you take a map if you intend to do this, as most of the park is very natural second-growth forest, and you can't always see your destination.). I would recommend to anyone doing the loop that they also take the short branch trail over to Beaver lake and back – it's a beautiful walk up a stream bed, and makes a nice addition.
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The first photo shows the entrance to the park near our hotel.
Other excursions
Bicycling
Bayshore Bicycles & Rollerblade Rentals - Denman
Address: 745 Denman Street
Vancouver, BC V6G 2L6
Email: info@bayshorebikerentals.ca
Phone: 604.688.2453
Fax: 604.264.9820
URL: www.bayshorebikerentals.ca
Spokes Bicycle Rental & Espresso Bar Inc.
Address: 1798 Georgia Street West
Vancouver, BC V6G 2V7
Email: info@spokesbicyclerentals.com
Phone: 604.688.5141
Fax: 604.681.5581
URL: www.spokesbicyclerentals.com
Kayaking
I, John Fereira (~jaf30@cornell.edu) plan on renting a kayak from Ecomarine on Saturday around 4:00pm for a couple of hours. Tours with Ecomarine require prior reservations and to be paid in advance. If anyone is interested in a kayak tour on Sunday morning (we'd have to be back by the afternoon pre-conference session) please send me email and I'll try to organize things. Anyone is also welcome to join me for a two hour Saturday afternoon outing. I've been sea kayaking for about 10 years and teach locally on occasion so I can provide some informal instruction/tips.
Ecomarine Ocean Kayak Center
http://www.ecomarine.com/ <== convenient to Westin
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Equipment Rental Rates
(Discount: Buy 4 single 2 hour rental coupons and get one free.)
Deep Cove Canoe and Kayak
http://www.deepcovekayak.com/ <== about 1/2 hour away
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