If there's one thing we love about Apple's annual Macworld show it's the ability to generate its own hype, weeks before anything has actually been announced.

With so much secrecy surrounding every single Apple announcement and a global audience of fans whipping themselves into a frenzy over every perceived hint, it all makes for good sport.
Something in the Air

This year is certainly no different. As Steve Jobs adds the final touches to Tuesday's keynote speech, the Apple rumour mill is in overdrive once again. Especially since a number of giant banners with the words "There's something in the air" were spotted hanging from the rafters of the Moscone Center in San Francisco over the weekend.

A lot of rumours claim that the banner purports to the impending announcement of a size-zero subnotebook... a MacBook so light it floats. The MacRumours.com website has even suggested that this new notebook is to be called the MacBook Air. This new portable will reportedly lack an optical drive and employ 1.8-inch solid-state Flash memory (64GB?) instead of a standard 2.5-inch hard-disc drive in its quest to shave off some extra fat. We'll see, we'll see.

Another explanation for the banner could be the introduction of WiMAX into Apple laptops, and possibly even the rumoured size-zero MacBook. Businessweek.com notes that Apple chipmaker Intel "loves" the long-distance wireless connection technology. The only problem, as Valleywag.com points out, is that beyond Intel and Sprint in the US, WiMAX currently has little support.

Maybe Apple is about to change all that. But what's the point of a WiMAX-equipped notebook without widespread WiMAX coverage?
Spinning the rumour mill

Another popular rumour doing the round is that the banner refers to an impending announcement of an improved version of AppleTV, with the ability to stream rental movies from the iTunes store. Of course, sales last year didn't hit the giddy heights Apple had hoped for, but maybe Steve Jobs can see something in it we can't.

Then again, maybe it's a 3G version of the iPhone. We'd certainly settle for that.

Other slightly more quirky suggestions we've seen over the past few days include Apple Airlines, Apple-Nike branded trainers, an Apple hoverboard and wireless electricity for all Apple products. Ouch. There's even been some speculation on one message board that the slogan refers to a joint bid by Google and Apple for the 700MHz spectrum! That's extremely unlikely, but out there in Apple-land, nothing is ever quite impossible.

Check back tomorrow and all will be revealed. It's probably all hot air anyway... Ouch!