The left needs to stick together. I think it was Roemer who said it earlier this evening, and I think he's right. GroenLinks, D66 and SP need to hold their own, and resist the temptation of forming a coalition. Maybe this way the left can get a majority alongside VVD without CDA, but then again VVD will probably demand another centre-right party, so VVD + CDA + D66 + GL seems like a more realistic scenario.
But for the sake of discussion, how does a coalition of VVD (33) + D66 (19) + GL (14) + SP (14) sound on paper? 80 seats. Assuming all parties that excluded to rule with PVV stick with that promise, there wouldn't be a good majority possible if D66/GL/SP stick together, or it has to be a 5 or 6 party coalition, but I'm not seeing that happen.
NOS has a nice little tool to mess around with forming coalitions, pretty fun.