If you want a notebook with a 14.1" screen or smaller the IBM's are great choices but they are pricier for what you get. They have some of the best keyboards in the business and they are built to withstand more harse use and vibration, etc then some others. Some even have a built in keyboard light for use in low light conditions.
However, many college students want the notebook to perform as a DVD player, etc (and even be used as a TV with a TV card). Thus, the 15.4" notebooks are very popular and still can weigh in the 6-6.5 pounds range (and still be carried around in a notebook backpack like Targus that will hold a 15" screen).
Any decent Pentium M (Centrino) notebook will get 3.5-4 hours using wi-fi or playing DVD's and more than that when not using wi-fi.
Note that you can get a Student discount through HP/compaq, a $100 rebate on any custom notebook, and possibly even a $100 coupon depending on the model. And, if you learn about Fatcash you may be able to get another 3% cash back later.
I highly recommend for 15.4" Pentium M notebooks the compaq X1000 series/HPZT3000 series (same notebook, only appearance difference) or the Toshiba M35S456 with the new Trubrite LCD screen.
you can easily configure the HP/Compaq with all necesary options (get at least the 1.6 Pentium M Dothan cpu in any event as it has 2x the system cache of older chips -- 2mb L2 system cache) for between $1000 and $1500 with all the options.
Keep in mind you can save on system RAM (you should get at least 512mb total) by ordering only 256mb from the manufacturer and getting another 256mb or 512mb from Crucial or Kingston, etc later.
See X1000forums.com for information on the compaq/HPZT3000 or see the Toshiba website for the M35S456 - it is more expensive because it has a DVD burner --you will probably be fine with a CD-RW/DVD ROM but you can add this custom if you want. Toshiba can be ordered custom as the M30 also but I don't know about student discounts, etc.
note, the HPZT3080 (with DVD burner and 1.7 Dothan Pentium M), the Compaq X1480 (same specs as above) and the Toshiba M35S456 (similar to above with Trubrite screen) can all be tried out at Circuit City if you want a prebuilt (I bought my X1360US there) instead of ordering custom).
All of these notebooks have 64mb dedicated video memory which is important as notebooks cannot alter their video memory later like a desktop.
I'm seriously considering buying a notebook for school. I want a notebook that is very portable and has 4hour + battery life. I like the IBM X40, but will this laptop work decently for accessing the Internet and using the word processor on a daily basis? What alternatives are there to the X40?

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