Nintendo is probably the company who has released more IP's in the last 10 years... sadly, people only buy the main franchises...
just to mention a few:
-Trace Memory
-Drill Dozer
-Geist
-Chibi-Robo
-Hotel Dusk
-Disaster
-Endless Ocean
-Captain Rainbow
-Zengeki something
-Flingsmash
-Steel Diver
-The three "Operation Rainfall" RPG's
-Pushmo
-Dillon
-Wonderful 101
and I'm sure I'm missing a lot.
2004
Daigasso! Band Brothers
platform: ds
developer: nintendo sdd
2005
Nintendogs
platform: ds
developer: nintendo ead 1
Another Code
platform: ds
developer: cing
ouendan
platform: ds
developer: inis
Brain Training
platform: ds
developer: nintendo sdd
sennen kazoku
platform: gba
developer: indieszero
nonono puzzle chalien
platform: gba
developer: creatures, inc.
chibi-robo
platform: gamecube
developer: skip, ltd.
geist
platform: gamecube
developer: n-space, inc.
the legend of the quiz tournament of champions
platform: gamecube
developer: ???
2006
odama
platform: gamecube
developer: vivarium, inc.
rhythm tengoku
platform: gba
developer: nintendo spd 1
Drill Dozer
platform: gba
developer: gamefreak
Calciobit (Nintendo Football Club)
platform: gba
developer: ???
Bit Generations
platform: gba
developer: skip ltd
Electroplankton
platform: ds
developer: indieszero
Elite Beat Agents
platform: ds
developer: inis
Tingle's Rosy Rupeeland (Spin-off IP)
platform: ds
developer: vanpool
Wii sports:
platform: wii
developer: nintendo ead 2
wii play
platform: wii
developer: nintendo ead 2
2007
wii fit
platform: wii
developer: nintendo ead 5
Hotel Dusk
platform: ds
developer: cing
2008
wii music
platform: wii
developer: nintendo ead 2
Endless Ocean
platform: wii
developer: arika
Captain Rainbow
platform: wii
developer: skip ltd
Disaster: Day of Crisis
platform: wii
developer: monolithsoft
Fossil Fighters
platform: ds
developer: red entertainment/m2/artdink
2009
Tomodachi Collection
platform: ds
developer: nintendo spd 1
Style Savvy
platform: ds
developer: syn sophia
2010
Art Academy
platform: ds
developer: headstrong games
Xenoblade Chronicles
platform: wii
developer: monolithsoft
Fluidity
platform: wiiware
developer: curve studios
FlingSmash
platform: wii
developer: artoon
Zangeki no Reginleiv
platform: wii
developer: sandlot
Line Attack Heroes
platform: wiiware
developer: grezzo
2011
Steel Diver
platform: 3ds
developer: nintendo ead 5/vitei
Pushmo
platform: 3ds eshop
developer: intelligent systems
Pandora's Tower
platform: wii
developer: ganbarion
The Last Story
platform: wii
developer: mistwalker
Sakura Samurai: Art of the Sword
platform: 3ds eshop
developer: grounding inc
2012
Dillon's Rolling Western
platform: 3ds eshop
developer: vanpool
Ketzal's Corridors
platform: 3ds eshop
developer: keys factory
Kiki Trick
platform: wii
developer: nintendo spd
Nintendo Land (Spin-off series)
platform: wii u
developer: nintendo ead 2
Sing Party
platform: wii u
developer: freestyle games
2013
HarmoKnight
platform: 3ds eshop
developer: gamefreak
The Wonderful 101
platform: wii u
developer: platinum games
NES Remix (Spin-off series)
platform: wii u
developer: nintendo ead 2
2014
Rusty's Real Deal Baseball
platform: 3ds eshop
developer: nintendo sdd
Captain Toad: Treasure Tracker (Spin-off Series)
platform: wii u
developer: nintendo ead tokyo 2
2015
Code Name: S.T.E.A.M.
platform: 3ds
developer: intelligent systems
Splatoon
platform: wii u
developer: nintendo ead 2