Prepare yourself, there's a lot! Just be careful you don't overdeal it.
Groupon - Still the best. Still the most well presented. And now with the Groupon app, the easiest to use.
Living Social - Almost irrelevant now. Many deals are out of Boston, and they have way to many coupons for Brazillian blowouts (weren't those declared toxic?) and yoga classes.
CoupMe - They often have really amazing massage deals, but the rest of the deals are bunk.
BuyWithMe - Getting better and the cool thing is that their deals often last a week, so you can sit on it and decide if it's really worth it.
DigDeals - Great rotating sale of actual gift certificates that get mailed to you. Not a big selection, but always quality places.
Yelp Deals - Just launched this week. Not sure how frequent they're going to be or how good, but the first deal was $50 for a massage. Not bad.
Bloomspot - A higher end deal site, like stays at a French country inn, or limo rides.
Eversave - Most deals tend to be in the suburbs. Lots of spa deals.
KGB Deals - Questionable name. They had $6 movie tickets on sale, but now it looks like they haven't officially launched in Boston yet.
DealOn - Not launched yet.
Zozi - Local, National and Travel deals for around the world. They mostly sell hotel coupons and deals for activities like kayaking in Baja or photography classes in Boston.
Plum District - Mostly geared towards moms, but recent deals have also included Target gift cards and Bruegger's Bagels.
Tippr - Looks like they just steal deals that others have done.
Homerun - Well designed site. Looks like most of their deals are for small things like a $2 pitcher of sangria at Tasca or a $2 glass of wine at Davide's.
Dealster - Many are outside of Boston, but there's some amazing deals like $30 for 4 oil changes.
DealsforSchools - Some decent deals, like $30 for two facials, hair cut and pedicure. Bonus is that part of the proceeds go to schools!
Sites that bring together all the deals: