Please try to break my web site

I'm really proud of this web site. It has taken me hours and hours of work, and it is capable of quite a bit of database editing. Now I want you to try to break it, or at least find bugs.
Until the end of July the site will use the Microsoft Northwind Traders database, a clump of test data used by programmers to develop and test database applications. You should have full editing rights to all records, so screwing up the data doesn't count as a bug, unless it breaks the web site somehow.
I am also looking for feedback on how intuitive the site is, and how easy it is to use the features. I'd also appreciate constructive comments about the layout, styling, and so on. Remember that the site is trying to look plain and simple, because the data is the most important part. You can visit the site at www.fishwisepro.com.
It uses Microsoft IIS7 and ASP.NET 3.5, together with a really cool web control called ASPxGridView from www.devexpress.com. The site is hosted by www.webhost4life.com in the USA. If you manage to break it, please let me know what you did. If you are using a browser other than Internet Explorer 8, Mozilla Firefox 3.5 or Google Chrome 2.0.172.37, then let me know if it does anything weird. Thanks in advance

Update: Testing is over. Thanks for all who helped. I will post another version of this site at www.mustang.co.za at some point.

As the mafia would say: if you breaka my site, I smasha your face!