Overall, we have had pretty good experiences bringing our own wine to restaurants. Restaurants that are wine-friendly tend to do nice things like waive corkage on certain nights of the week or waive corkage on a bottle if you buy one of their bottles. We do the math and it's usually worth it and we get to bring some wine home.
We recently had dinner at Bistro 29 in Santa Rosa. We were there early and they were advertising $10 off each bottle of wine. They also waive their $15 corkage if you buy a bottle. After checking with our server that we could get BOTH the $10 off and free corkage, we bought a bottle of Truchard Roussanne for $36 (net to us was $11) and opened a bottle of Rhys Alpine Vineyard Pinot Noir that we had brought.
Even if a restaurant does not waive corkage, their attitude can convey wine friendliness. The last time we were at Gary Danko in San Francisco the sommelier complimented our wine saying, "we can't even get this." If a sommelier is interested, we typically offer him/her a taste of our wine.
Next up, some not-so-good experiences in bringing wine to restaurants.