CHRISCHRAM  Under Snow Leopard this version of Monolingual does something to its preferences file that causes the application to crash after a number of runs. deleting net.sourceforge.Monolingual.plist and then resetting personal preferences fixes things for awhile, until next time. I just tried locking the preferences to see if I get better mileage. Time will tell.  
(Version 1.4.1)

MORGANG  The text on this download page says it works on Tiger, but after downloading it and trying to run it, I get a message saying it does not work with my OS version. Does it now only work for Leopard and Snow Leopard? Bummer.  
(Version 1.4.1)

CHRISCHRAM  Under Snow Leopard: This version seems to go off to never, neverland about half the times I use it. It barberpoles for a really long time, never finding any language resources to delete. When I finally give up and hit the Cancel button, the application crashes.  
(Version 1.4.1)

ROBERTCOOGAN2  Caused all sorts of problems on my iMac. After running it, it made Safari, Mail, iCal, and Firefox all crash upon launch. Went back into Time Machine and restored the system. Tried running it again, only with the same results. Plus, the second time around Adobe PhotoShop caused (what I think was) a kernel panic twice. The system froze and became unresponsive and the screen dimmed almost like a windowshade was being pulled down.

Best bet: don't install, don't run at all. Unless you are totally committed to removing language files that granted you may not use, but when you consider the size of the files you are dealing with here, it makes little if any difference if you remove them at all.  
(Version 1.4.1)

ACURAICE  I have been using this program for years! Has always worked flawlessly. Not sure why the developer has released this update for Snow Leopard, when I just used this program days ago without any errors, including to remove the additional unnecessary architectures in Snow Leopard with the slightly older version. Not sure exactly whats been updated, but as for being compatible with Snow Leopard, it has been. Keep up the great work! I would have gladly paid for this program and all of your had work.  
(Version 1.4)

TR2  Excellent utility, but my wish list:

a SELECT ALL or

a SELECT ALL except english AND AN OTHER LANGUAG

and i wish that after selecting all i want deleted ONE TIME

would stay like that everytime i launched the program

It's quite redundant to have to add all the checkmarks

time and time again. I'd like the program to remember

the last setup so we didn't have to add check marks

every darned time.   
(Version 1.4)

MITCH_DE  Best Tool to remove not needed language file. It find much, much more than XSLIMER and also its much easier to remove them as XSLIMMER.

I would NOT use Monolingual to remove PPC/Intel Code - that XSLIMMERs work, more safe (Blacklists).

Also check always before STARTING the preferences : remove ONLY foreing languages - NEVER ALL ENGLISH, NEVER yoor LOCAL language.   
(Version 1.4)

THEL  Love the app! However, the min req's stated here seem to be incorrect, as of this latest release. http://monolingual.sourceforge.net/index.php states that version 1.4 "requires at least Mac OS X 10.5 (Leopard) and also works on Mac OS X 10.6 (Snow Leopard). Version 1.3.9 is the last version for Mac OS X 10.4 (Tiger)."  
(Version 1.4)

PHOTOLINKONLINE  Excellent utility, but my wish list:

a SELECT ALL or

a SELECT ALL except english

and i wish that after selecting all i want deleted ONE TIME

would stay like that everytime i launched the program

It's quite redundant to have to add all the checkmarks

time and time again. I'd like the program to remember

the last setup so we didn't have to add check marks

every darned time.  
(Version 1.4)

SNOWWHITESICKETTE  Monolingual works well. I used it to remove some of the junk I don't need that clutters up my hard drive. I ran Monolingual to remove each of the three nuisance types it helps you delete. (Languages, keyboard layouts, and architectures.)

When running languages, I unchecked all English options, but I probably would have been fine just leaving English and US English unchecked. Got rid of all keyboard layouts I'll never need, as well as the Intel binary that just clog up my hard drive. Everything was smooth, fast, and worked perfectly.

I was so happy with the results, I ran Monolingual on two more Macs that day. Each Mac had good results, and for each Mac the process was fast, trouble-free and uneventful. Nice app, but people who don't read instructions before diving in, or who don't know what the keyboard layout or architecture type they are deleting is used for, should tread with caution. (Based on reading some of the comments.) Intel binary is nothing I need running a PPC, and deleting it isn't going to cause a problem. But for Intel Macs, I suggest learning about Rosetta and why you might not want to delete PPC code if you don't know if it serves a purpose. Backing up the disk ahead of time is a good idea.

I believe Monolingual could be used to make a DIY optimized version of an application. For instance, if you have a G3, you can remove the architecture for the G4 and G5, as well as Intel and others. I'm going to try optimizing some of my larger Universal apps and see if it helps. I always back up my hard drive with SuperDuper! before doing anything like this, just in case.

Monolingual saved 180MB on one Mac, 250MB on another, and 750MB on the third Mac I tried it with. I always do a custom install when I install OS X, and leave Additional Languages, Printer Drivers and Additional Fonts unchecked. I think the point updates sneak the languages back into the system, because Monolingual found stuff I know I deliberately did NOT install in the OS.

Monolingual worked as advertised for me, and freed up valuable disk space.   
(Version 1.3.9)