L. Vilkončius is a productive and versatile composer who has created a number of works for choir, orchestra, and ensembles. He wrote the children's opera "Paukštė", the ballet "Peter Pan" (based on the libretto by V. Palčinskaitė), the rock opera "Eglė - žalčių karalienė" (based on the libretto by S. Geda).

Wrote music for twelve theater plays and eight films ("Rich, Poor...", "Journey to Paradise", "Chameleon Games", "American Tragedy", animated film "Baub", "Grandma's Tale", etc.).

He organized the festivals "Sing group Jazz" in Panevėžys and "Baby Jazz" in Vilnius, led and sang in a vocal trio (with his daughters). He recorded the original CD "Požeminės upės", the CD and cassette "Tau, mano meile", the CD "Neregētas Vilkončius" with the state choir "Vilnius".

L. Vilkončius wrote more than 90 songs ("Will you save my love", "Laivas", "O mes skubam", "Dideli njštukai", "Mažos mašinėlės", "Kattis bveleleim židoint", etc.).