My Password was reset by the genius bar

I had to have my software reinstalled a few weeks ago, and they were so kind to do it at the genius bar. Unfortunately, they never told me what my admin password was. I haven't been able to download or update anything.

any idea what they generally reset it to? It was weeks ago and i have no idea what the guys name was and the stickers that came on the computer when i picked it up didn't say anything.

better yet, any idea how to reset it without knowing the current password? I live in Boston but i am in Australia for 4 months and really don't want to go through the trouble of taking it to an apple store here.

thanks!