ngrep was around ~9-10 years ago, I'm pretty sure of it
pv is not a command, it is a CLI app. You have to install a package for being able to use it.
sshfs is not a command, it's a generic name for a network filesystem
You claim to be a gentoo user, yet your question is stated in a "send me codez" manner. It looks like it's asked by somebody who thinks that knowing command names is the silver bullet. No, using your brain is the silver bullet.
I strongly recommend you to read (again, even if you already did it before) How To Ask Questions The Smart Way, because I think your question certainly doesn't meet those standards.
If I would have to compare Linux today and Linux 10 years ago, I would emphasize the following main differences:
access to internet is widely available now, even in some not very developed countries. This is a double edge sword: the amount of sane and adequate tech guys has increased greatly, but the percentage of them among all internet user has decreased. If you learn to avoid people that don't share your interests and hang with people that share common interests with you, you'll learn a lot from them. Even StackOverflow/ServerFault/SuperUser sites illustrate this perfectly.
much more people are writing free software. If 10 years ago sourceforge and freshmeat were unique and SVN was the king of version control, today we have github, launchpad and bitbucket, we have a lot of distributed version control tools, we have a huge amount of communities developing software or simply exchanging knowledge. Today, if you need free software for a certain particular task and you are being persistent enough, there are high chances that you will find something that suits you perfectly. Or something that suits you "almost perfectly" and you will end contributing and giving back to the community.
Edited to include the answer to your question from the comment:
I wonder what in particular you didn't like with this questions and how could I improve it?
I didn't like that your initial question is way too general.
Usually you try to complete a particular task, you try to achieve a very special goal. You try it one way, you try it another way, you go to review some man pages and still fail. This is the moment when you go asking for help and advices. You describe your workflow, the expected result and what you actually get. Don't be ashamed to admit that you tried something and failed. People are generally nice and helpful, most of them won't point fingers and tease you, most of them won't downvote you for failing. Some of them will even warn you about a poorly stated question, accepting the risk to be downvoted themselves for pedantry :-)
Stating your workflow is useful for a couple of reasons:
- readers of your question have to make less assumptions, because they would already know you tried X, Y, Z and it didn't work
- the way you state your question allows others to estimate your level of knowledge and provide an answer that would be easy for you to understand
Here are a couple of situations:
- you need to use a sniffer to debug a networking issue. You try tcpdump (which btw was the standard 10 years ago and nowadays shares the title with wireshark), you find its output too cryptic, its default values of options not very user-friendly. Somebody suggests you ngrep, you run it, you see that it provides more user friendly output by default and you learn a new thing.
- you do cp -a to copy a big directory, you want to see progress and you need to stick to command line, not even midnight commander is available. You read the manpage for cp and you fail to find the proper options. Then somebody tells you about pv.
- you aren't happy with ftp, because it transfers the data without encrypting it, you also want to edit files "remotely". Somebody tells you about sshfs, which "maps" a remote directory to your local filesystem over an encrypted connection.
See, these are your ngrep, pv and sshfs. Is there a difference between your general questions and my scenarios? Certainly yes. I will try to explain why. So you asked people to tell you about cool commands. You got 3 answers. Someday you might need to use a sniffer. And you will probably remember this question and will use ngrep. What if you get 1000 answers suggesting 1000 new commands? Don't you thing that a huge part of them will just slip through your memory for a short time period, then you'll forget about them? That will certainly happen, because when you gain new knowledge, you need to practice applying it, to get experience. Frankly, your initial question reminds me the situation when a kid tries to learn martial arts by looking at pictures in a book :-)