While Balagopala , Kamakshi swarajati and Enadi Nomu are truly mindblowing , Upacharamu by Maharajapuram Santhanam is equally good . But I feel nothing can beat the Viriboni varnam . There was an LP of R.K Suryanarayana playing Viriboni -truly mindblowing . Also , one must listen to N Rajam and Sangeetha Shankar playing Viriboni - (yes.. they have given a commercial recording of Carnatic Music ) simply superb..
What about " Koluvvaiyya" sung by the great MMI. His swaras @ ' manasu' no body can beat it!!!