Very odd.  I can't think of anything I did besides making some page edits, but all of a sudden, fckeditor stopped loading.  I'd just get a blank #xEditingArea and the following js errors:

Error: unterminated parenthetical
Source File: http://www.xram.net/Providers/HtmlEditorProviders/Fck/fckeditor/editor/js/fckeditorcode_gecko.js
Line: 48, Column: 4068
Source Code:
assName.replace(/(^| )FCK__ShowBlocks/g,'');else B.className+=' FCK__ShowBlocks';if(FCKBrowserInfo.IsIE){try{FCK.EditorDocument.selection.createRange().select();}catch(e){}}else{var C=FCK.EditorWindow.getSelection().focusNode;if(C.nodeType!=1)C=C.parentNo

Error: FCKConfig is not defined
Source File: http://www.xram.net/Providers/HtmlEditorProviders/Fck/fckeditor/fckconfig.js
Line: 2

Source File: http://www.xram.net/Providers/HtmlEditorProviders/Fck/fckeditor/editor/fckeditor.html?InstanceName=dnn_ctr816_EditHTML_teContent_teContent&Toolbar=DNNDefault
(the same file for the rest of the errors)

Error: FCKBrowserInfo is not defined
Line: 125

Error: FCKConfig_LoadPageConfig is not defined
Line: 164

Error: FCKTools is not defined
Line: 176

Error: FCK_ContextMenu_Init is not defined
Line: 195

Error: FCKLang is not defined
Line: 203

Error: FCKBrowserInfo is not defined
Line: 270

Error: InitializeAPI is not defined
Line: 210

I looked around and the advice to upgrade to the latest fck provider seemed like a good idea, as well as going from 4.9.1 to 4.9.2.  Still, same problem.  I've disabled the iFinity url provider, cleared the pageblaster cache, cleared my browser's cache, copied the exact configuration from the install.txt into my web.config.  I can't think of what else to do.

I appreciate greatly any thoughts, tips, or help on this.

At the risk of overwhelming you guys with too much info, here's the debug data:

FCK DEBUG INformATION DATA (English only):
------------------------------------------
DNN Version=4.9.2
FCK Provider Version=2.0.3.22447
ModuleId=816
ModuleType=
DNNUserId=1
InstanceName=teContent
ApplicationPath=Nothing
Image Folder ID=-1
RootImageDirectory=/Portals/xramnet/
ToolbarNotExpanded=False
ToolbarStartExpanded=true
TBE-I-KEY=DNNFCKI#TBE#Edit#teContent=
TBE-M-KEY=DNNFCKM#TBE=
TBE-P-KEY=DNNFCKP#14#TBE= False
FCK-Config= ToolbarStartExpanded=true&FlashBrowserWindowWidth=700&fckSource=false&StylesXmlPath=/Providers/HtmlEditorProviders/Fck/FCKeditor/fckstyles.xml&LinkBrowserWindowHeight=340&ImageBrowserWindowWidth=700&CustomConfigurationsPath=/Providers/HtmlEditorProviders/Fck/custom/FCKConfig.js&FlashUploadURL=/Providers/HtmlEditorProviders/Fck/fckimagegallery.aspx?type%3DFlash%26command%3Dfileupload%26tabid%3D288%26rootfolder%3D/Portals/xramnet/%26currentfolder%3D/&ToolbarCanCollapse=true&EditorAreaCSS=/Providers/HtmlEditorProviders/Fck/FCKeditor/editor/css/fck_editorarea.css&SkinPath=/Providers/HtmlEditorProviders/Fck/fckeditor/editor/skins/Office2003/&ImageBrowserWindowHeight=600&PreventSubmitHandler=true&ImageBrowserURL=/Providers/HtmlEditorProviders/Fck/fckimagegallery.aspx?FCKTheme%3DDefault%26type%3DImage%26tabid%3D288%26rootfolder%3D/Portals/xramnet/%26currentfolder%3D/&LinkBrowserURL=/Providers/HtmlEditorProviders/Fck/fcklinkgallery.aspx?FCKTheme%3DDefault%26tabid%3D288&DefaultLanguage=en&AutoDetectLanguage=false&FullPage=false&ImageUploadURL=/Providers/HtmlEditorProviders/Fck/fckimagegallery.aspx?type%3DImage%26command%3Dfileupload%26tabid%3D288%26rootfolder%3D/Portals/xramnet/%26currentfolder%3D/&FlashBrowserURL=/Providers/HtmlEditorProviders/Fck/fckimagegallery.aspx?FCKTheme%3DDefault%26type%3DFlash%26tabid%3D288%26rootfolder%3D/Portals/xramnet/%26currentfolder%3D/&FlashBrowserWindowHeight=600&LinkBrowserWindowWidth=400

Good ideas, but sadly, no luck.  I set the admin skin and container to the basic DNN blue, wiped the entire FCK directory and reuploaded it from the latest release, and did the same for the dll in /bin.

Still no dice--same problem.  I'm going to try going back to an earlier release of fckeditor and see if that clears anything up.  Is there anything in the database related to fckeditor I could clear?  In HostSettings, I see a lot of DNNFCKP#{portalid} entries.  If I wipe them, will they be recreated?  I have no idea how they could have been changed, but denial doesn't get my site working again :)

True, true.  It was an idea, but I didn't think it would work either.  No matter--I didn't get a chance to do it, because I had another idea.

I disabled PageBlaster, cleared it's cache, cleared DNN's cache, cleared the browser's cache, rinsed, repeated, and *bam* it worked.

I then reenabled PageBlaster, cleared all caches again, and it still works.  Something somewhere wasn't letting go of whatever was causing the problem, but repeated cache flushes finally got it out.  Definitely something on the server, since 3 different browers on 3 different computers did the same thing.

And as a bonus, it taught me that the automated backups done by my hosting company DO NOT WORK.  Luckily, I had created a manual backup after I noticed it was a problem.  I had them roll my site back to the previous night's automated backup, and all of a sudden, my site appeared as it had a month ago.  Some bug in the database backup script.  So, even though it isn't directly related to the fckeditor error, TEST YOUR BACKUPS (EVERYBODY)!  You'd be amazed how often they don't work.

And, as always, thank you Sebastian for your voice of reason.