From data gathered by rovers and satellites exploring the surface of Mars, NASA has developed some cool web applications where everyday people could explore the surface of the planet.
One such application is called Mars Trek. This is a free web-based application allowing people to explore the surface features of the planet. It uses real data gathered from 50 years of Mars exploration. You could navigate the surface of Mars in 2D or 3D, using a mouse or standard keyboard game controls. Clicking on a land feature will give you basic information about it. There are drawing tools letting you draw lines and boxes on the planet, as well as measure distances and elevation changes. You could even export a 3D model of a land feature to print with a 3D printer.
NASA team uses this tool to search for possible landing sites for new 2020 rover, as well as for human exploration planned in 2030's.
Experience Curiosity tool let's you play around with the Curiosity rover on Mars. You could spin around it, use its tools, click any spot on the planet to make it drive there, drill a hole... Driving and drilling actions are sped up many times, so you don't have to spend an entire day watching it drive to a nearby rock, like it does in real life.
Living in the 21st century is cool. When else where people able to explore a neighbor planet from the comfort of their home?