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list block devices
Shows all block devices in a tree with descruptions of what they are.

Crash bash, in case you ever want to for whatever reason
This is a very hackish way to do it that I'm mainly just posting for fun, and I guess technically can more accurately be said to result in undefined behavior. What the command does is tell the shell to treat libpng like it's a shell plugin (which it's most certainly not) and attempt to install a "png_create_read" command from the library. It looks for the struct with the information about the command; since it's always the command name followed by "_struct", it'll look for a symbol called "png_create_read_struct". And it finds it, since this is the name of one of libpng's functions. But bash has no way to tell it's a function instead of a struct, so it goes ahead and parses the function's code as if it was command metadata. Inevitably, bash will attempt to dereference an invalid pointer or whatever, resulting in a segfault.

List every file that has ever existed in a git repository
What was the name of that module we wrote and deleted about 3 months ago? windowing-something? $ git log --all --pretty=format:" " --name-only | sort -u | grep -i window

Check if your ISP is intercepting DNS queries
It's somewhat common ISPs to intercept DNS queries at port 53 and resolve them at their own. To check if your ISP is intercepting your DNS queries just type this command in the terminal. "#.abc" it's an OK answer. But if you get something like "I am not an OpenDNS resolver.", yep, you are beign cheated by your ISP.

Prints the latest modified files in a directory tree recursively
Sorts by latest modified files by looking to current directory and all subdirectories

Gathering all MAC's in your local network
replace eth0 with your ethernet or wireless network interface.

rename all files with "?" char in name
replace all "?" characters in filename to underscore

Parallel mysql dump restore
this command works with one gziped file per table, and restore 4 tables in parallel.

Salvage a borked terminal
Also works in places where reset does not.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }


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