Swagbucks activities that seem the most profitable right now

1. SBTV, oddly enough, is probably the most consistent source of high earnings. I first checked it out a few years ago when I first got Swagbucks, and realized it was earning me 1-2 Swagbucks for several minutes of clicking stuff. No thanks. But then I read somewhere online that you can add videos to your favorites, and then the app will autoplay your favorites list repeatedly while you do something else. The shortest videos at the moment are in home and garden, and the titles include the phrase "10-second tips." Add at least two of these to your favorites, hit play, and go do something else. Once it says you've earned your 10 SB for the day, ignore this, and let it keep running. It will allow you to earn a random number of bonus Swagbucks each day, ranging from 4 to 38 so far in my experience. If you do only this activity, you should be able to get a $5 Amazon gift card every 15 days or so.
2. Coupons: You can print out the same coupons as coupons.com has from the Swagbucks site under "coupons." You earn Swagbucks when you redeem them, usually credited about a month afterward. If you already use coupons, print them on Swagbucks instead of on coupons.com. If you don't, and don't typically think it's worth the effort, you can still print out the ones for products you buy anyway, and then you'll save money and earn Swagbucks. I've also heard of people printing them out and leaving them near the product in the store, or putting them on bulletin boards in laundromats and similar places.
3. Referrals: I told you, it's a pyramid scheme. Post your referral link on blogs, on social media, and tell friends about all the cool free stuff you get. Just don't be obnoxious about it. People on various websites have also mentioned using free business card deals to print out their referral link on cards and then leave them on bulletin boards with some sort of tagline about how you can earn gift cards and cash.
4. Shopping deals: Use these for things you were already going to buy. There are ones that earn you X number of Swagbucks per dollar you spend on various websites, and some that involve making an in-store purchase and then e-mailing a picture of the receipt. There are also deals that give you a number of Swagbucks for making a purchase. Remember that a Swagbuck is roughly one cent, so there are some that earn you money or get you a free item or service. Reddit keeps a running list. Remember to read the fine print about what you actually have to buy or how long you have to keep subscribing to the service in order to earn the Swagbucks, and remember to cancel the service if applicable.

EDIT (05/24/16): The "sign up and earn" links under "Discover" are also pretty good. A lot of them just require you to click through, enter your e-mail address and make a password, and then you get 50 Swagbucks. I just did Kellogg's coupons and Zulily. 

And of course, if you haven't signed up yet, use my referral link please. Thanks!