Booking site?
 

Out of curiosity, what site do you guys use to book your flights and why?

Do you use the same for hotels?

99.9% of the time, the airline or hotel company site.

Main reason is accountability and direct access to help when things go wrong.

Also complies with terms to receive points, stay credits, and bonuses.

Who needs to insert a third party into the mix, for a supposed marginal savings?

Simple as that.

Check out the Travel Tools forum here.

I'm more curious what people are using rather than a list of tools :)

The Travel Tools Forum is the appropriate venue for your query. Please follow this thread as I move it to that Forum.
Thanks..
Obscure2k
TravelBuzz Moderator

Booking directly will get you the best price nowadays on most airlines with just a couple of exceptions such as perhaps the legacy Japanese carriers or some airlines in China.

The reason to book through an agent would then be not for the lower price but if you can't get the same itinerary booked directly through the airline.

However, as @Non-NonRev pointed out, in case of any flight changes you'd be forced to deal with the same agent, who might be difficult to contact over the phone.

Unless the deal is very good, this extra layer of complexity is not worth it.