Second, if you need to leave the table for any reason, but want to maintain your claim to it, leave easily replaceable personal items on the table and take your laptop and other valuables with you, even into the bathroom.
Third, don't appear to have an expensive laptop. That Apple logo screams "black market retail value!," so buy a cover that makes it look like a cheap laptop, or something other than a laptop.
And fourth, confuse crooks with the unexpected. Most criminals are looking for specific things — wallets, high-end smartphones, expensive laptops and iPads. I walk around wearing Google Glass with confidence. Nobody is going to steal it because that technology is not on their radar yet. Criminals are confused about what it is, so they leave it alone. Likewise, you can confuse crooks by making them unsure about what you've got.
I'm a huge fan of Twelve South's BookBook line: Phone, tablet and laptop cases that look like old leatherbound books. This will at best make them think you've got a book and in the worst-case scenario confuse them before they figure out that you've got some unknown type of electronic device. That delay in reaction makes a big difference.
Nobody wants to steal your book. They'll never know your "book" is actually an iPad wearing a Twelve South BookBook cover.
How to get good Wi-Fi
The quality of Wi-Fi connections vary wildly around the world and tend to be very bad in most countries. It's common for the staff at restaurants and coffee shops to know nothing about the network. Often either the router or the Internet connection isn't working, and nobody knows or cares why.
Always check for actual data throughput by connecting and doing something before you sit down. Check performance by loading a picture.
Favor hotels over other establishments because their Wi-Fi is usually more reliable. Performance in hotels varies by location, so walk around to find the best spot before checking in, then request a room closest to the Wi-Fi sweet spot.
Carry a long Ethernet (RJ45) cable and plug-in for a wired connection to the router if you can.
If your cable can't connect to the router, try rolling your own Wi-Fi network with a wireless travel router. I recommend the Asus WL-330NUL All-in-One Wireless-N150 Pocket Router because it's tiny, and also light enough to hang from a router (which is often wall-mounted). Be bold. Just step right up to the router and plug in. The proprietors will most likely shrug and forget about it.
How to get mobile data easily and cheaply
I can answer that question in three words: Switch to T-Mobile.
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