When I can get a seat, Bluehouse is hands-down my favorite wi-fi equipped coffeehouse in the city. I'll linger for hours over pots of tea and my Macbook Pro. If I happen to be there over lunchtime, the pre-made sandwiches are pretty good too! They also have Kettle Chips, and several vegan baked goodies (though if you're not vegan, these probably can't compare to the good 'old butter+sugar variety).

A few tips:
Try to park on Bluehouse's side of the street. This side is free, whereas the other side is not.

Tea drinker? Try the mango nilgiri, it's a fragrant and strong black tea. Many of the people behind the counter are big tea (and coffee) fans too, so ask for recommendations.

Start a tab! Depending on who's at the register, they will either plug your name into the computer, or start you on your very own post-it note of drinks, etc. Just leave your credit card until you're ready to pay.

There's a big seating area past the drinks counter, but there's also a smaller one with a couch up front. Check both ends, if one seems crowded. Wi-fi seems equally reliable in both areas.