I can give you some idea of what my hard drive looks like, though: 37 GB total, 27 GB free.
I have Windows XP Pro Service Pack 2, Office Pro 2003, Photoshop CS with ImageReady CS, Visual Studio 2003 Professional, Encarta 2004 (hard drive install), and only about 500 MB of personal data on the hard drive. I do have a 1GB page file, and a couple of ISO files I need to burn to CD. So I've got about 2GB that's not normally there. But I store most everything on a server. So if you included those things:
Music 23.5 GB
Downloads 7.5 GB (Operating Systems, programs, betas, drivers, etc)
Documents 1 GB
Pictures 1.7 GB
That's 33.7 GB just in data. So I'm over 40GB just in things I use. Now granted, I'm not about to store my 300-album MP3 library on the laptop when I can stream it easily over my wireless network. But if you plan on using this for your main computer, and want to do these things with it, count on needing a 60GB hard drive.
I am looking (now) at the thinkpad T41 or T42. Will be using mainly for work-email. Most of the models that I can afford come with 30GB HD. How much do I need? I have been looking for articles on the subject, with no luck. Any thoughts?

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