I don't get on that well with the Clarins one - it makes my tinted moisturiser pill into little lumps (nice).
Quite similar (i.e. silicone-based - so make skin feel very smooth) but not so prone to pilling on me are Estee Lauder Idealist, and Clinique Pore Minimiser (the latter has a bit of colour so is a bit like a foundation in itself).
Laura Mercier primer is a bit different, it's not so much a skin 'refinisher' as something that is supposed to make your makeup stay put longer, although I don't notice much difference (yesterday I did a half and half test on my face and really couldn't tell which side had the primer on by the end of the day).
If you can get hold of Chanel's Le Blanc de Chanel grab it, it is the business, but it is not always available.
If you wear eye makeup, esp shadow, then eye primers are REALLY good - Urban Decay's primer potion is good but packaging is crap; Too Faced's Shadow Insurance is nearly as good and has much better packaging.
sorry, that was a bit of an essay, can you tell I've been pondering the same thing myself recently!