Here is my list:
Marriott Rewards Premier Visa Credit Card: As a Marriott enthusiast whose goal is to become Lifetime Platinum this card is a no brainer. The annual Category 5 certificate more than offsets the $85 annual fee and the Elite nights and credits earned helps me get closer to Lifetime Platinum. This is the card I use the most.
Ritz Rewards Card: The 140k signup offer was too good to turn down. Annual Fee is $395 but the benefits of the card more than offset the fee. Each calendar year you get the $300 airline credit + $100 Ritz hotel credit in addition to airport lounge access, and 3 Ritz club level upgrade certificates, plus trip insurance and roadside assistance.
United Explorer Card: Recently signed up for this card as I plan to move away from Delta and take more advantage of the Marriott partnership with United. Annual Fee is $95. Perks include 2 United Club Lounge passes each year, Free Checked Bags (perk I already receive for being Plat), Miles never expire while your a card holder plus additional award availability with no restrictions or blackout dates. Was able to get a 50k mile signup bonus.
Delta Platinum Amex: Planning to cancel card this card before it renews since I'm flying less with Delta now. Annual Fee was raised from $150 to $195 last year. Perks of the card included free checked bags and annual coach companion certificate. Earlier this year I obtained the Southwest Companion Pass which is now making this card less useful to me. Definitely will replace with another Amex card as Amex Deals are awesome.
Bank of America Better Balance Rewards Visa: Originally signed up for this card when I needed to buy lots of things for my new home as I was able to get 15 months no interest on purchases at the time. Card has no annual fee but also gives you $25 each quarter when you pay more than the minimum payment. I use the card now just to pay my cable bill each month and collect the $100 yearly reward.
Discover Platinum Card: Great card with no annual fee with lots of Cash Back Earning opportunities. Primarily use this card around Christmas time to take advantage of the 5% or higher Cash Back offers. Free Fico Score.
Barclay Arrival Plus Card: Excellent sign up offer good for $440 in travel credit. Card has a return of 2.3% return on purchases if using points for travel. Free Fico Score. $89 Annual Fee but free membership to Tripit Pro which helps offset the annual fee especially if Tripit Pro helps finds you airfare refunds for your travel.
Ah, vaboywnder, you've got quite a collection going.... I've dramatically consolidated over the last few years, including giving up my UNITED card: