I 'graduated' to Barclays online banking from their telephone banking system. I was a little late coming over as their first attempts were for PCs only and I use a Mac, however this version works well providing you use IE5, for some reason they don't like Netscape.
I have two Barclays accounts and so I can transfer money between them very easily, I also pay all of my bills, eg telephone, credit card, council tax via their online banking system. It is very simple and gives you an accurate balance on your account at any time of the day or night.