Sudoku

This sudoku puzzle that suddenly finds itself all over the daily newspapers is quite the addicting puzzle (for those of you who are unfamiliar, you have a 9 x 9 grid that is subdivided into 3 x 3 grids - the object is to put the numbers 1 - 9 such that each 3x3 grid has each number once and each row and column has each number once).

I tried it for the first time on Sunday and it took me quite a long time before I realized I had made a mistake and had to start over. :(

However, last night before bed, everything fell into place and I finished one. It made me feel quite good until I realized it was 1130 and I should have been in bed an hour ago. Puzzles sharpen the mind. I hope. :)