Here at The Switch, we love it when our writing sparks a new idea or raises a new question. So that's why, every weekend, we pull together some of the week's most thoughtful comments in one place.

Friday, my colleague Timothy Lee reported on a massive bitcoin transaction amounting to $150 million. That prompted our reader Frazil to ask why bitcoin exchanges often offer varying price quotes.

Here's what I don't get. There seems to be a large difference between bitcoin prices on the various markets For example at Mt. Gox bit coins are currently trading at $724.80 per bitcoin, while at bitstamp its $846.00 per bitcoin. That seems to be unbelievably huge arbitrage opportunity. If fact too big to be true. What am missing.

Michael Frank replied:

That price difference persists because it is extremely difficult to actually do the arbitrage, since Mt. Gox's banking relationships in the U.S. were terminated by the Feds, so it's difficult to get US dollars out of Gox and into the US. To do this you would probably have to shuttle the funds around through Japanese banks and/or by way of other intermediate currencies. This process is expensive (the banks will take a cut at each step) and so that's why the price difference persists.

On Thursday, the government said it was considering allowing air travelers to make phone calls from cruising altitudes. While our commenters seem to hate the idea of letting annoying chatter onto airplanes, krobin had a helpful suggestion: separate talkers from non-talkers:

If cell phone use is allowed on flights, I hope they include that as an option for seat selection as they used to do for smokers and non-smokers. In other words, put all the cell phone users in the back of the plane and let them yak it up. And let those of us who want to read, rest, converse (in a normal tone of voice) or get some work done sit up front. Anyone sitting up front who wants to use their cell phone or the toilet knows where they can go do that.

In response to my colleague Andrea Peterson's deep dive on Valve, the company that wants to change the gaming world, reader Kmtierney reflected on Valve engineers' biggest innovation:

The PC gaming industry is a pretty fascinating one, in that you have a few companies (Valve, CD Projekt Red, Rockstar etc etc) who have thrived by realizing that their playerbase is not just their customers, but a constant focus group you can poll on how to tailor the product (also being very mod friendly), whereas the old game behemoths like EA, Blizzard et al think they know what's best for you, games aren't mod friendly, and they have been suffering a lot lately.