Bananarama - Love Don't Live Here: I expected this to chart low, but its #114 peak was crap. I found this song miles better than Love Comes, the lead single (which only peaked at #44), and they actually promoted it quite a lot on TV, even if radio airplay was nonexistent. Such a nice pop song.
Girls Can't Catch - Keep Your Head Up: This was one of the top tunes of 2009 for me. Never understood why it charted so low (#26). In fact, "Echo" charting higher was even more surprising, although I love this group.
Kleerup featuring Titiyo - Longing For Lullabies: Brilliant tune, although perhaps its similarity with With Every Heartbeat killed its chances.
And in a few weeks you can add:
The Pipettes - Call Me: Pull Shapes was a classic, and I haven't liked much the new lineup change, but this song is quite good and deserves to be a hit. it won't even crack the top 100 though, unfortunately.