Make a big file into many small files (and back again)

Adapted from this slashdot thread

Create many little files called "chunks00000" etc. from bigfile that are all just under 10MB in size: split -a 5 -b 10MB -d bigfile chunks

Put the chunks back together: cat * > newbigfile

Do the same, except with compression: tar -zc bigfile | split -a 5 -b 10MB -d - chunks

Put the compressed chunks back together: cat chunks000* | tar -zxO > newbigfile

VIM split windows and macros quick reference

ex commands for split windows

• :sp filename create a new split with filename
• :vsp filename create a new vertical split with filename
• :new create a new split with an empty buffer
  
• :vne create a new vertical split with an empty buffer
  
• :wa save all open files
• :wqa save and quit all open files

Ctrl-W related commands for split windows

• C-w h moves split to the left of current split
• C-w j moves split below the current split
• C-w k moves split above the current split
• C-w l moves split to the right of the current split
• C-w + increase the current split by one line (or, prefix this command with a number to do that many line increases)
• C-w - decrease the current split by one line (same addendum as above)
• C-w < decrease the current split width
• C-w > increase the current split width
  
• C-w _ Maximize the current split

Split windows in the .vimrc (taken from this page ... also see the same author's excellent Efficient Editing with VIM )

• map <C-J> <C-W>j<C-W>_ " Hit C-j to move the current split down and maximize it
• map <C-K> <C-W>k<C-W>_ " Hit C-k to move the current split up and maximize it
• set wmh = 0 " allow splits with 0 lines open

Macros

• q<register> start recording and save the macro in the specified register (use a lowercase letter, for example)
• q (again) end recording
• @<register> playback the macro