Something like "Cities I've visited" from TripAdvisor, but look more like some kind of porfolio.
I tried Foursquare, Google Maps and some other services, but here are why they don't suit my needs
Too bloat (advertising, clumsy interface)
All-in-one page (make a new trip, find the flight etc)
What I need is just some minimalist interface, with a nice map, and some markers there so that I can have the gallery of where I've been, put in some notes 'bout the experiences
Foursquare is probably the site that can do this - You'll need to "Check in" using Foursquare's mobile(web) app and it keeps a record of where have you been
You can create a personal maps on Google Maps (and on Bing Maps as well, I think). Google allows you to add pins in certain shapes to either countries, cities, specific addresses, or even GPS coordinates, with whatever data you want to add. Once you save it, you can make your map public, private or share it with specific people. E.g. here's one of my maps from last year.
I believe Where Are You Now? is the best one.
It allows integration with your contacts, places you have been to, what you know about the places, pictures, videos, who is traveling where, if you are planning a trip - who has been there before, local buddies, others locals traveling to the same spot as you are.