Cool Google Spreadsheet... (?)

Google already announced its acquisition of Writely, a web based word processor that enables you to edit, save, share, and real-time co-edit Word (-like) documents through a web browser from anywhere in the world (... eh... you'll need an internet connection), and we already saw Google Calendar (which together with Gmail replaced Outlook for me). Then we saw Google Pages, a great web based web page editor that even my mom can easily use, and the google-labs version of Google Notebook which allows you to annotate (segments of) web pages for public or private use (exactly what I have been waiting for...). But now, Google comes with a google-labs version of Google Spreadsheets, which is, no surprise, a web based spreadsheet program. It's really quite cool and promises a lot for the online word-processor (=Writely?) that they have in preparation. It's limited compared to OpenOffice.org's Calc program, or Microsoft's Excel, but it's better than the Excel version I have on my PDA: apart from crunching numbers and statistics with an extensive range of math-, stats-, financial-, date- and string-functions, formatting, sorting, importing and exporting from and to excel or csv, it allows me to collaborate with colleagues in real time on a single sheet, while 'talking' to each other with a messenger service as in your Gmail account. Thank god I have a Gmail account! How unfortunate that I don't use spreadsheets a lot, nor do my colleagues... :'(