If you just meant this ctag feature ,also gedit has a plugin for that: 
http://www.stambouliote.de/tarballs/gedit_classbrowser-0.0.3.tar.gz

but I really miss this feature to have quick every method and property 
of an object in front of my eyes. anyone knows any editor for ruby which 
supports that?

-- 
greets

   	   		                (
	  		                    )
			                   (
			            /\  .-"""-.  /\
			           //\\/  ,,,  \//\\
			           |/\| ,;;;;;, |/\|
			           //\\\;-"""-;///\\
			          //  \/   .   \/  \\
			         (| ,-_| \ | / |_-, |)
			           //`__\.-.-./__`\\
			          // /.-(() ())-.\ \\
			         (\ |)   '---'   (| /)
			          ` (|           |) `
			    jgs     \)           (/


one must still have chaos in oneself to be able to give birth to a 
dancing star