Help me identify this flower, err, weed!

My backyard has more weeds than grass. Some of the weeds are actually beautiful little purple flowers.They mow easily and grow back quickly. I think I might just like to encourage more of these to appear and not worry so much about the lack of proper grass in my backyard.

Gardeners! Any notion of what they are and how I can get more of them to take over? Are there sites where I can just punch in a detail or two and it will spit out an identification?

Update: The consensus seems to be that they are wild violets, so no flame throwers are needed. Thanks for the advice, everyone!

Comments

[Kim]

I don't know what they are, but we have them too. If you do nothing they will spread naturally. You might also find more dandelions and other weeds becoming more prevalent in your yard too though. Andre wants so badly to get rid of all the weeds but I think, who cares, it's still all green!

[Fae]

Violets. I wish I could get them to take over my yard, too!

[Amy]

Ooh, I wish they were violets, but a friend just let me know it's probably Creeping Charlie. The pretty flowers will go away leaving ugly Charlie behind. Time to get the flame thrower!

[Jennifer]

Creeping Charlie. I highly recommend the "is this plant a weed?" tool here:

http://www.extension.umn.edu/Garden/

Of course, you can usually make an argument in support of weeds. Apparently in the UK they grow creeping charlie as a groundcover. Personally I think it smells wonderful.

[Fae]

Creeping Charlie has rounder, scalloped leaves, and smaller flowers. Those are -Viola sororia- in the photo :)

[Jaime Chismar]

This is definitely NOT creeping charlie. Creeping Charlie is a relative of the mint family. These are violets and I'd toatlly leave them in your year. I did!

[Amy]

Will the purple flowers stick around, Chis? If they are violets, how do I encourage more of them?

[K.B.]

Those are violets, not Creeping Charlie. If you do a google image search for both, you can see the differences.

As for helping them stick around, try to get rid of them. That seems to increase any weed I'm trying to get rid of :)