http://en.wikipedia.org/wiki/File:DNA_sequence.svg
if you look the above image, you'll see that in one instance three A's are together. How is that possible? i thought A binds to G and T binds to C
I think you are confusing the hydrogen bonding between two strands of [R/D]NA which, as you say, is A:G and T/U:C, and the chemical bonding in each strand, which could be any combination or permutation of A, C, G, and T/U.