In 2005 Janne joined forces with former Sir Lord Baltimore drummer/singer John Garner and the two formed John Garner's Sir Lord Baltimore. A toured was planned, but unfortunately various (mostly economical) obstacles made it never happen. The two however recorded a new version of Sir Lord Baltimore's "Woman Tamer".
In 2007 Stark joined forces with Björn Lodin and Mikael "Nord" Andersson in a completely new band called incarnation called BALLS. The band's debut album Chameleon was released on October 10, 2008, but the band folded shortly after its release. Janne and Mikael are still composing songs together. Janne also contributed with guest guitars on releases by Thalamus, M.O.B, Alyson Avenue and Tower Of Stone. Stark also started collaborating with Token/Scudiero keyboardist Mikael Rosengren in what was to become the band Constancia, who released their debut in 2009. Late 2011 Janne joined melodic rockers Grand Design.
In November 2013 Janne's third encyclopedia, "The Heaviest Encyclopedia of Swedish Hard Rock and Heavy Metal Ever!" was published. It features information about 3600 Swedish hard rock/metal bands on 912 pages.
In 2016 Janne released the third Mountain of Power album and also started collaborating with American singer/bassist Neil Merryweather. The debut of Merryweather Stark is set to be released end of 2017.