You only need 50 reputation to comment anywhere on the site. That's only 5 upvotes on a good answer or 10 upvotes on questions. It's an extremely low bar to get over.

Note: You can always comment on your own posts (questions or answers).

Well it is a barrier that has stopped me participating too. It is very easy to dismiss these when you, and all those around you, are beyond them.

It's a shame that that's kept you, and probably others out. Honestly I think it's worth it to have some small barrier, but whether it's helping much is debatable- there's still been a pretty bad downturn in the quality of content in some areas over the past couple years.

The 50 reputation barrier only stops you from commenting. It's a spam prevention measure. Anyone can answer a question (even anonymously) with 1 reputation. Anyone who registers can ask a question.

It's extremely frustrating when you want to comment on a different Stack Exchange site but can't due to having no reputation... despite the fact that the new account you made is 'linked' to one on Stack Overflow with thousands of rep.

If you have thousands of reputation on SO then you should get the 100 point bonus on every site where your accounts are associated. If you don't have it, open a support post on Meta (http://meta.stackoverflow.com/questions) and we'll try to see what's up.

I only have 477 points on SO, yet when I sign up for other stack exchange sites I immediately get 100 free points. The bar really isn't that high. It's just designed to force newbies into those specific activities that one ought focus on first: providing good answers to questions, and asking good questions.

Judging by my reputation history the best way to reach the 50 points needed to leave comments is (perhaps unsurprisingly) to write some answers! I suggest you find some unanswered questions under tags with which you're familiar. I actually think the system works quite well; most SO comments are worth reading. One peculiarity of the privileges that I've found is that I'm not allowed to make edits with fewer than 6 characters. I've had to leave some pretty significant typos uncorrected.

Yeah, this thing with the typos must be improved. Quite often it's a matter of 1 or 2 characters.

Just a point of clarification: users who can edit immediately (those over 2000 rep) can make edits of any length. The length limit is enforced for "suggested edits", which need to be approved by two other users and for which the editor earns +2 reputation.

I agree, often I've wanted to add something, but I'm unable to because I haven't participated enough.

I'm on the wrong side of the chicken and egg, so I just leech.

Welllll...it takes, approximately, three to five useful answers. Note that they don't need to be The Answer To Life, Universe, And Everything; they don't need to be the longest, or fastest, or best-looking answers to that question - just useful.

I've run a tiny experiment on SO: http://stackoverflow.com/users/779183/friar-tuck - it took me, from "logout and clear all cookies" to "Commenting privilege unlocked", twenty-five minutes (1500 seconds) of wall-time, start to finish; no cheating, no sockpuppetting - just answering three (3) easy questions in a mildly useful way and watching the upvotes roll in.

Alas, "I come to the __Q&A__ site 'often', but can't be bothered to __ask__ or __answer__ anything at all, how come they deny me privileges?" sounds a bit more entitled than "the System keeps me down and prevents me from commenting," doesn't it?

I didn't mean to sound entitled, it's not a big deal to me (and others if I was to hazard a guess).

Normally when I hit SO I'm stuck and often it's not on my dollar. I always intend to go back and add something, but when I do have free time, I like to get away from the computer and thus I never end up contributing.

Well, that's pretty much what many SO's users do; and there's nothing wrong with that :)

I have misunderstood your previous post, then, and I'm sorry for that - I thought you were complaining that getting the privileges is too hard.

Check out the 'featured' tab and see if you can answer something. Easy way to unlock commenting, and several other privileges. Or just post a few good answers, you'll be able to comment the next day.

Good advice. This is usually something I try to do, but invariably some context switch happens and...hey cows!

It is nice to give back if possible though.