How to read large text file on windows?

A lot of the answers here helped point me in the right direction, however none were suitable for me, so I am posting my solution.

I have Windows 7, which comes with PowerShell built-in. Here is the script I used to find/replace all instances of text in a file:

powershell -Command "(gc myFile.txt) -replace 'foo', 'bar' | Out-File -encoding ASCII myFile.txt"

To explain it:

• powershell starts up powershell.exe, which is included in Windows 7
• -Command "... " is a command line arg for powershell.exe containing the command to run
• (gc myFile.txt) reads the content of myFile.txt (gc is short for the Get-Content command)
• -replace 'foo', 'bar' simply runs the replace command to replace foo with bar
• | Out-File myFile.txt pipes the output to the file myFile.txt
• -encoding ASCII prevents transcribing the output file to unicode, as the comments point out

Powershell.exe should be part of your PATH statement already, but if not you can add it. The location of it on my machine is C:\WINDOWS\system32\WindowsPowerShell\v1.0

Update
Apparently modern windows systems have PowerShell built in allowing you to access this directly using

(Get-Content myFile.txt) -replace 'foo', 'bar' | Out-File -encoding ASCII myFile.txt

I discovered git-annex recently which I find awesome. It was designed for managing large files efficiently. I use it for my photo/music (etc.) collections. The development of git-annex is very active. The content of the files can be removed from the Git repository, only the tree hierarchy is tracked by Git (through symlinks). However, to get the content of the file, a second step is necessary after pulling/pushing, e.g.:

$ git annex add mybigfile
$ git commit -m'add mybigfile'
$ git push myremote
$ git annex copy --to myremote mybigfile ## This command copies the actual content to myremote
$ git annex drop mybigfile ## Remove content from local repo
...
$ git annex get mybigfile ## Retrieve the content
## or to specify the remote from which to get:
$ git annex copy --from myremote mybigfile

There are many commands available, and there is a great documentation on the website. A package is available on Debian.