There are several acts named Valentina.
1) Valentina is an Italian-British singer/songwriter residing in London, UK.
"A floating, ethereal world away from the alt-dance world inhabited by the Hot Chip musician, it's a delicate and beautiful collection of songs that range from hazy, electronica to piano-driven, pop minimalism." -- Glamour magazine
2) Valentina is a Brazilian glam rock band from Goiania, GO, formed in 2003. They mix influences from various indie bands like Placebo, Yeah Yeah Yeahs and Interpol and also some from the Brazilian pop rock scene, like Pato Fu, Ira and Titas. With Rodrigo Feoli on vocals, the band has released their first demo.
VEJA, a Brazilian magazine, relate an episode when Valentina has opened a Placebo show in Brasilia, Brazil. When they ended their presentation, Brian Molko's secretary asked Rodrigo Feoli which eye liner he was using in his eyes.
Rodrigo Feoli (vocals)
Angelo Carlos (guitar)
Marcelo Tannus (guitar)
Paulo Tiballi Jr (drums)
3) Valentina is the alias used by Elena Ferretti for the Eurobeat label A.Beat-C. She is known for the songs like 'Occasional Dream', 'Your Love', and 'Harmony.'