Short answer: definitely absolutely not. Get a portable monitor or a stationary monitor instead and save a ton of money.

Long answer:

My dad used to have a thinkpad with a similar feature, the Thinkpad W700ds. W=workstation-tier, 7 = 17" screen, 00 = Core 2 Duo G3, ds = dual-screen

Basically it was an extra half-sized screen that slid out on the right side. It wasn't super useful, but it was pretty sweet. That being said, the thinkpad W-series computers were tanks, they were monstrosities. Basically portable desktops. I loved them.

If you're doing the starving grad student thing and really need extra screen space, you should just buy a couple monitors. Spending $400 on some extra screens for your laptop attached like that is ridiculous. You could spend $200 and buy two of these big honking 21" HD monitors: (newegg link) and be drowning in screen space. Then spend the extra $200 on ramen or whatever

If you absolutely MUST have portability (say you can only work in coffeeshops or something) you can drop your number of megapixels from 2 to 1 and get a usb-powered-and-driven portable 16" monitor for a similar price, so 2 for $200: (amazon link). I personally don't like portable screens but my sister has used one of these and she liked them. I think these come in 2-megapixel versions (same as the slidenjoy) for $130 each?

In any case, spending $400 on the slide n joy is like spending $150 on a fancy holster for a portable screen, or if you use your laptop as a desktop, spending $200 to get worse, smaller screens. I would never purchase this unless it was super duper seamless and I was lazy and had a lot of cash. Since you're a starving grad student, it's worth it for you to deal with the portable screen problems (ie, not having a nice holster / carrier, etc) to save $200. In fact you're probably like the worst sort of person to use this item, since you're resourceful and intelligent but poor; this is an item for people who don't have a lot of time to deal with it and are rich.

Make sure to order through some service that lets you return them if you don't like them, like Fry's Electronics or something. Kickstarter of course does not provide this.

So yeah definitely don't get that.