Linking to Word, Excel etc

Is it better to use file:// or http://?

[tintin99]

I'm working on an intranet where there are several links to MS Office files which open the Word doc or Excel spreadsheet in the browser window.

Does it make any difference whether I use an http:// link or a file:// link for this? I realise the path will be different for each method and that using http:// has advantages in that I can use virtual directories, but are there any other differences I should be aware of?

[physics]

None that I know of...