Verified answer

These are all impressionist pieces, and very flashy and difficult

Ravel's Jeux d'eau

Ravel's Toccata from the Tombeau de Couperin (last mvt.)

The last Debussy Prelude "Fireworks" (Can't remember the French)

Debussy Images II, last mvt "Poissons d'or" (goldfish)

Debussy L'isle Joyeuse

Debussy Images I, Reflets dans l'eau (I think it's the first mvt.)

Edit: Wow, I guess that Muczinsky piece is getting pretty well-known. It's a very effective piece. Also, look into the Ginastera sonatas. Everyone plays the 1st one, but it's still cool. Also, maybe this? http://www.youtube.com/watch?v=KmdGbUzv4SM&feature...

with regards to 20th century, there's lots:

bartok

--allegro barbarto

copland

--passacaglia

ginastera

--danzas argentinas

--malambo

--suite de danzas criollas

liebermann, lowell

--garogoyles (a crowd pleaser and last mvt very difficult)

messiaen

--un reflect dans le vent from 8 Preludes

Muczysnski

--desperate measures

--toccata

prokofiev (lots of pieces by him):

--toccata

--3rd sonata

--diabolica suggestion

Shchedrin

--Basso Ostinato

Good luck! Let me know what ur program gonna be