Need breakfast in Marais to replace my Deux Magots habit!
I'm weaning myself off of the 6th, but I'm a fish out of water in the 3rd. I like to sit in the enclosed patio area of Les Deux Magots and have cafe, croissant, confiture, omelette, fromage, etc. etc. While certainly not the best bargain for breakfast in Paris, it is oh-so-comfortable, and the people watching is non-pareil, so if you can identify a similar experience in the Marais, I'd be very happy!
There is plenty of people-watching café in the upper Marais, only they do not the same type of people-watching. Definitely a younger and trendier crowd. My description will stop here.
Try Le Progrès (1, rue de Bretagne) and all the other cafés along the same street.
Around the Carreau du Temple, as Parigi said, is also a gold mine of breakfast/burger/brunch places. They do not make them any trendier than that but it is Marais style (chipped paint, wood floors, waiters in t-shirts, I'm-too-hip-to-stand-in-line customers, messy haircuts and lots of sunglasses - there, my description did not stop there after all), not the more aseptized Saint-Germain style.
My vote goes to Le Progrès though. A very nice place and the food (classic troquet fare) is not bad.
High end café like Les Deux Magots, are a rarity, even in Marais. The closest thing would be some palace breakfasts, but where are they in Le Marais? Jaques Génin is wonderful and comfortable, but there's little people watching (unless you're into food bloggers...) and he does not really do breakfast. I would say Le Victor Hugo on Place des Vosges, maybe with pastry from very nearby Gérard Mulot could do.