Copied from tinySpell Homepage:


Occasionally you need to check spelling in an application that does not include a spelling checker and you don't want to launch your word processor just for that. This is when tinySpell becomes handy. It is a small utility that allows you to easily and quickly check and correct the spelling in any Windows application. 
tinySpell can watch your typing on the fly and alert you whenever it detects a misspelled word. It can also check the spelling of text that you copy to the clipboard. tinySpell installs itself in the system tray for easy access.
It comes with an American-English dictionary containing more than 110,000 words.


Features:


Checks spelling in any Windows application 

Checks spelling on-the-fly (alerts if the last typed word was misspelled) 

Checks spelling of text that is copied to the clipboard 

Allows you to specify applications for which tinySpell is disabled or enabled 

Optionally beeps on error (beep sound can be easily set to any wav file) 

Optionally displays a spelling tip (see example) 

Provides easy access to on-line web services 
(Search, Dictionary, Thesaurus, Encyclopedia)

Opens replacements list with a simple mouse click or a hot-key 

Optionally copies the selected replacement word to the clipboard 

Optionally inserts the selected replacement word into the document 

Allows you to add words to the dictionary 

Easy Enable/Disable 

Uses little system resources