One should be very careful buying a laptop because more than desktops there are big differences in the technology and feature sets that matter. Run-down of tech issues:

'True portable' versus 'desktop replacement' tech:

There are at least two major divisions of tech in laptops: tech designed for laptops and tech designed for desktops but used in laptops.

Laptop tech results in smaller, lighter, cooler-running laptops that last longer on their batteries. Only downside is they are a lot more expensive.

Desktop tech results in larger, heavier, hotter-running laptops that have shorter runtimes on batteries before they need to be recharged. Of course they are cheaper, sometimes a LOT cheaper, than true portable tech laptops.

There are likely one or more classes of laptops that would most accurately be categorized as in between these extremes.

Telling the difference:

On the Intel side, anything labeled "Centrino" is true-portable; but there are non-Centrino true-portables too. The biggest factor is the CPU: the "M" for Mobile after the processor, as in Pentium M or Celeron M, is a huge difference; the chips are barely related to the Pentiums in desktops. They are really good tech, getting a lot of performance for a little power, and a lot per clock. So a 1.5 GHz Pentium M sounds slow but it is more like a 2.25 GHz desktop Pentium 4 or better. Do not compare the two without multiplying the P-M/C-M speeds. These laptops often are visually recognizable by being thin & sleek.

Any laptop labeled 'Desktop Replacement' or DTR is one based on non-portable tech. They are best for those on a budget and/or where the machine will spend most of its time sitting in one place plugged in to a wall, or just moved around within a house like between a bedroom and the living room couch. The true portable tech is worth it if you will be using the machine on the road a lot or lugging it around in a backpack or carry case. DTRs look fat (say, around 1" thick, keyboard to desk, not including screen) and clunky by comparison with the true portables.

In the desktop world AMD is kicking Intel's butt but in the laptop world it's the other way around. AMD has a portable tech called 'Turion' meant to compete with Centrino but it's not quite as good. If on the other hand you are buying a DTR, AMD is probably better because Intel desktop chips run hotter and perform poorer, especially in games. Also all current AMD models are 64-bit capable for future operating systems.

In the middle:

Just to confuse things there are intermediate chips: the 'Mobile Pentium' and 'Athlon64 Mobile'. These are in between on the DTR/portable spectrum in price & performance, as you would expect. They are more closely related to desktop tech than portable tech, tho. Also beware of buying older tech like Pentium III or Athlon XP-based notebooks; if anyone is still selling these pay bottom dollar.

Graphics & gaming:

Laptop graphics are notoriously slow. But for RTS, it may not matter. Still the low end may be slow enough to impact the latest RTS's. This is one area where DTRs just blow away true portables. They can come with graphics chipsets from NVidia or ATI that compete with decent add-in card desktop graphics. Pentium M / Celeron M laptops usually come with Intel graphics, which is slow. Turion laptops are probably faster in graphics than P-M/C-M's. Find out the graphics chipset the laptop you are interested in uses and check out on-line reviews to see if anyone benchmarked an RTS on it, to see if performance will be acceptable. Graphics becomes a LOT more important if you plan on playing any modern shooters on the machine.

Other stuff:

- steer clear of any Transmeta CPU based laptops (slowww).

- never buy a laptop with less than 512MB RAM if you can afford it; Windows XP runs slow in 256M. Prefer a laptop upgradable to at least 1GB.

- buy XP Professional if you plan on ever logging on to a corporate network

- I care, but you may not, for video out. I can load a laptop's hard drive with movies & recorded TV MPEG files and use it as a portable video jukebox. Some laptops have S-Video out ports built-in, some don't.

- Some laptops, especially smaller ones, require an expensive and / or easy to lose adaptor to plug into an external monitor. Prefer one with a standard VGA or DVI out port.

- Smaller laptops often omit an optical drive. I wouldn't want to get one without a DVD burner, for back-ups and stuff, but that's just me.

- Some laptops include FireWire/IEEE1394 ports for hooking up digital camcorders. Also can be used as a high-speed file transfer / network port if your desktop has FireWire (400MBps = 4x Ethernet, unless both have Gigabit Ethernet).

- You want at least 'b & g' wireless support; having no 'g' is obsolete. 'n' or 'pre-n' is cutting edge.

- Some laptops include built-in card readers for uploading photographs from your camera quickly.

- All new laptops should include USB 2.0.

- Laptop speakers are always crappy. You can get an awesome pair of JBL Duet speakers for <$20 shipped on eBay, from the JBL repair dept. Also JBL has an excellent foldable, portable speaker set called 'On Tour', prob. also avail. on eBay cheap refurb.

Final advice

Don't buy a laptop! That is, buy one if you absolutely need portability, inside or outside the house. If you can stand to have a desktop instead, remember that desktops are superior to laptops in every conceivable dimension, including what you get for your money, except portability, They can even take less space in a room & on a desk than a laptop. Many people think laptops are cool or cool-looking, only to find out that they either didn't really need the portability or that the laptop caused a lot more headaches than a desktop would have. Note that you will replace a laptop likely years before you would have replaced a desktop bought with the same or less money. A desktop is more reliable, more flexible, cheaper, more expandable, higher performance, more future-proof, and can be quieter and take less space. If you know all that then by all means buy a laptop.