It is columbine, Aquilegia species......most folks consider it a very desirable garden plant although it does have a tendency to seed itself around a bit.

Thank you for the help! =) It seeding itself around would explain why it seemed like a weed!

When it reseeds you may not get the same colour combinations. Yours is Aquilegia vulgaris and it can produce single, double, plain, shaggy, pink, white, dark pink and purple and bi-coloured flowers. But they're all pretty.