lots of good stuff, the stuff I use already off that list:
I use a programmer's editor which doesn't know anything about JavaScript other than how to color code it. (Which one doesn't matter, and starts holy wars, but if you're curious, I use ConTEXT - http://www.contexteditor.org/.)
Yeah I use http://www.contexteditor.org/index.php.
It has Highlighters you load including ones for Cisco IOS, Powershell, MS SQL, VbScript, Batch files, SNMP (MIB), and more. It covers every scripting language I use.
It is freeware and has a portable version for on the go without installing.
I use the free text editor ConTEXT with the "Cisco IOS - colorful" (direct download link) highlighter. It automatically saves backups in a configurable backup directory. If some other app changes the file while ConTEXT has it open it will prompt to ask you if you want to reload the most current version.
Also rather than pasting back into the session I use a TFTP server. I use Zoc which has a simple scripting language. I wrote a script that will upload the current config as a backup file name to my TFTP server with the current date and time, then it will TFTP copy the config I'm working on to the current switch, then save it, then upload the "new" version back to the TFTP server.
It's especially handy for ACLs since as you probably know if you try to edit an ACL live, it'll append to the end of the ACL which may screw up your order. So my ACL config files have a "no access-list 120" at the top then rebuild the entire ACL 120 for example. I add lines with just "!" in them to break up ACLs into sections - they don't get parsed on the actual switch config but keep my ACLs clean on the text file on the TFTP server.