Tokyo Side Trips

Any suggestions for Tokyo side trips?
The places which i have already planned for and/or do not want to visit because I have been to: Kamakura, Yokohama, Nikko, Hakone, Five Fuji Lake, Kawagoe.
Ideally the transport not to be too expensive ...any suggestion pls let me know.

Is the Tokunai Pass an unlimited train pass for JR inside Tokyo? Am i allowed to use it on both JR Yamanoto and JR Chuo line?

What kind of things are you interested in?

You could visit Omiya for the train museum, bonsai, and a nice shrine. You could go to Gunma for onsen and a world heritage site (Tomioka Silk Mill). You could go to Mito for Kairakuen garden, or a few stations further to Hitachi Seaside Park for a huge park and great flowers (dependent on time of year of course). Izu is doable in a day trip for beaches, waterfalls, and wasabi. Go to Chiba for a cute retro train line, coastal views, and a neat lighthouse. I like Yamanashi for nature, a great hike through a gorge, and Japanese history in Kozu. If you like or are interested in pottery, Tochigi has some kiln tours that I've heard are really great.

But in the end giving your preferences of things you like to see helps narrow it down for us giving suggestions. Otherwise we're just shooting in the dark as to what you like.

Is the Tokunai Pass an unlimited train pass for JR inside Tokyo? Am i allowed to use it on both JR Yamanoto and JR Chuo line?

Full details here: http://www.jreast.co.jp/e/pdf/tokunaipass_e.pdf

Enoshima
Nokogiriyama
Takaosan
Niigata prefecture, e.g. Echigo Yuzawa
Etc......

Kairaku-en in Mito, Hitachi Seaside Park in Ibaraki-ken.

How about Kanazawa?

The new Hokuriku Shinkansen taking 2.5 hrs combined with a JR Pass make Kanazawa a doable day trip from Tokyo.