So, Sony is the latest to be breaking records today with the official launch of what the company considers is the world's lightest notebook. Naturally, that all rather depends on whatever woolly boundaries there are between net and notebooks but the fact remains that an 11.1-inch screen, 0.72kg and 13.9mm is pretty damn ultra portable. Naturally, not everyone's going fancy the Vaio side of the equation, so here are five other options for computing on the go.

MacBook Air (19.4mm, 1.36kg, £1349)

Yes, it's an obvious one so let's get it out of the way now. The Air was one of the first laptops to tell optical media that it just didn't care any more and whatever you say about the machine and the annoying envelope ads, it does have a lovely form factor. Unlike the Vaio X, it comes with a proper processor - an Intel Duo Core 2 - at either 1.86 or 2.1GHz, integrated 256MB Nvidia GeForce 9400M graphics, 2GB of DDR3 and a 120GB SDD if you want to go for the top end model. The full dimensions are 227 × 325  × 19.4mm and even though it's still a squeeze of a little backpack, you do get the benefit of an LED backlit screen with 1280 x 800 pixel resolution.

Dell Adamo (16.5mm, 1.81kg, £1899)

Until the Adamo came on the scene, it was Apple who held the crown for the thinnest. The luxury branded Dell has now set the bar at 16.5mm thick. Again, there's an Intel Core 2 Duo at the heart with a 1.6GHz clock speed and up to 4GB RAM to back it up. Keeping toe-to-toe with the Air, it has a 256GB SSD and a larger 13.4-inch LED backlit screen with 1366 x 768 resolution. Dell has obviously had complaints about the Adamo just not being thin enough, damn it, so, the company has being showing off the next generation in the saga. It's the truly size zero, 9.9mm Dell Adamo XPS. There's very little else known about it either because the Texas company can't work out how to fit anything inside it yet or because there's a long campaign of photos with it next to pencils planned. Again.

MSI X340 (19.8mm, 1.3kg, £720)

For those who aren't made of cash, one good option of a similar size is the MSI X340 - the current best combination of power and size that the company does. It houses a 1.4GHz Intel CULV processor, just the 2GB RAM and rather than an SSD, gives you 320GB of the old spinning disk kind of storage. It's no frills on the screen with a straight forward 13.4-inch LCD but the real weakness is probably the battery pack, which only offers 2-3 hours away from the wall. There's always the option of an 8-cell battery that's obviously going to add to its vital statistics.

Asus UX30 (19.6mm, 1.45kg, £999)

Asus has come up with a very similar proposition to the X340 with another CULV machine using the same Intel chip. It's a 13.3-inch machine - this time LED backlit and with a full 4GB RAM compliment to keep it running. Still, no optical drive but it does have a very decent array of ports on offer and up to 500GB of HDD which probably accounts for the added weight. Lovely simple form factor going on with a brushed aluminium finish. The only downside is that it's quite expensive given the lack of power on the graphics side. Just an integrated Intel GMA 4500M to play with.

Toshiba Portege R500 S5007V (19.6mm, 1.08kg, £950)

Not the world's snappiest name and perhaps not quite as stunning as some of these other models but for size and weight, it's up there with the Adamo and Air. That said, it is a smaller screen device and at a more comfortable 12.1-inches with an LED backlit screen. As a slightly older computer it comes with just 2GB of RAM and a 1.33GHz Intel Core 2 Duo U7700 processor. However, the real bonus here is that you also get the benefit of optical drive that'll re-write DVDs and anything easier.

If that lot doesn't tickle your fancy, then you,re probably after a netbook. That or a desktop PC.