TL;DR
Tools and techniques used to "break" hardware wallets demystified ...

"Why do I need to
careworry about technical details 'n' stuff?!" you might ask."I've been down with crypto currency for over a decade!" you say.
"Crypto is secure!" you say.
"I'm a crypto legend!" you say.
OK OK! I get it; you know what you are doing!
Scenario A:
Thanks to ALL that Blogging, You are Targeted

Please see/use: Hide Your TREZOR Wallets with Multiple Passphrases
Scenario B:
First, You Learned the Value of Decentralization ...

(w1nn1ng!)
Then You Learned the Importance of Cold-Storage ...

(w00t!)

(Bravo!)
Whoops, LOST that Shit!

(D0h!)
Order a Replacement via Amazin Drone ...

(nice!)
Call Grandma and Get the Necessary Key(s) ...

(WHEW!)
Reconfigure Hardware Wallet

(ahhhhh)
Continue Living the Dream

(YES sauce!)
What are Side-Channel Attacks?
Per Wikiedia:
"In cryptography, a side-channel attack is any attack based on information gained from the physical implementation of a cryptosystem, rather than brute force or theoretical weaknesses in the algorithms (compare cryptanalysis).
For example, timing information, power consumption, electromagnetic leaks or even sound can provide an extra source of information, which can be exploited to break the system.
Some side-channel attacks require technical knowledge of the internal operation of the system on which the cryptography is implemented, although others such as differential power analysis are effective as black-box attacks."
Common classes of side channel attacks include:
- Cache Attack
- Timing Attack
- Power-Monitoring Attack
- Electromagnetic Attack
- Acoustic Cryptanalysis
- Differential Fault Analysis
- Data Remanence
- Software-Initiated Fault Attacks
- Optical

Intro to Side-Channel Analysis Course

RSA Power Analysis Side-Channel Attack
Demonstration Against RSA (MUST watch. Reality happens @ 9:00)
Side-Channel Analysis Hardware Buying Guide
Breaking Bitcoin Board
@ DIY
If you aren't into soldering, a local shop ought be able to help you out.
ChipWhisperer-Lite (CW1173) Basic Board
@ $250.00 USD
If you love to solder or just on a budget, go for this is the entry level option from Mr. O'Flynn.

ChipWhisperer-Lite (CW1173) Two-Part Version
@ $325.00 USD
If you'd rather not solder (just how many more hours do you need to work to cover the additional $75?) and just "get to it", this step above the entry level option is a good balance of bang for the buck.

Side-Channel & Glitching Starter Pack (Level 1)
@ $550.00 USD
If you expect to be performing this type of research regularly, you might want to consider this package with a helpful few extras. The extras are available individually also so, you are free to build your test lab as you grow.

SAKURA-X
@ ¥ 370,000 (Roughly $3,500 USD!)
If you've secured Gov't funding, this might be up your ally!

Reference
Breaking Bitcoin Hardware Wallets @ DC25
Bitcoin hardware wallets security
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Steemit's Easiest Personal Setup Guide
Steemit's Easiest Witness Setup Guide
Steemit's Easiest EOS Setup Guide