As in title, I'm going camping with some buddies soon and we're planning on bringing far more beer than we have space for in a cooler. What kinds of beer are palatable to drink (or good even) when at room temperature or even slightly warm?
Somewhat related: What temperature should I serve my beer? In short, beers don't need to be served as cold as many are led to believe, and darker beers tend to be meant to serve warmer (as warm as 55°F). You certainly don't want to drink warm Coors, so maybe bring along some stouts.
In case there isn't a stream around to do what @user23614 suggests, bring some newspapers. Wet a sheet of newspaper and wrap the bottle with a single layer. Leave the bottle somewhere the breeze can blow on it, until most of the water evaporates. This is probably a common camping trick, but I first saw Moroccans in the Sahara Desert do this to chill a bottle of wine.
Short answer: no beer that has color-changing mountains on the side should be served warm, otherwise you'll taste it.
First, ales are traditional served warmer than pilseners, so start your selection there.
Second consideration is sweet/bitter balance. Sweetness generally becomes stronger with warmer beer. Something with a bit of sour would probably hold up well when warm. At the same time, styles that are meant to be sweet are usually served at/close to room temp: barleywines, or anything imperial/double/doppel/strong. Bonus: you won't have to carry as much.
Third: can you get it in a can? Cleaning up that campsite will be so much easier the next morning...
My first temptation is to say none. However there are two mitigation strategies to this dilemma.
The first is mulled beer, you need a light IPA, a saucepan, cinnamon and star anise. Put the beer in the pan, add the spices and heat.
The second strategy, and one I've used, is camp near a stream. Store the beer in the stream in a net bag or similar. Any beer works in this situation and it will cool the beer to a drinking temperature.
At room temperature the flavour of the beer starts to intensify, some people would say it gets more bitter. I tried something that worked: there are beers like Kingfisher Light that have pretty good carbonation content. So even at room temperature you get a good time. You can try any other beer that has strong carbonation and little mild in flavour.