Is there any way to store hollandaise sauce?

I believe it was in the same episode of Good Eats -- a good thermos.

If my memory serves correctly, Alton used a vaccuum flask, and pre-heated it by putting in hot water, dumping it out, then adding the hollandaise to hold. (but I don't know how long it'd actually hold in there ... if it's a well-made flask, it's possible it could hold the temp for a long time, but it'd proabbly be in the 'food danger zone' temperature between 40F and 140F.)

Not really. The sauce must be refrigerated but the butter will solidify when it cools. When you warm it up the sauce will break.

What I do is warm it very very gently in the microwave until it is liquid. Then reemulsify it into a single egg yolk. It costs an egg yolk but the sauce is good as new.

Hollandaise sauce made properly can be refrigerated over night and may be added to a new hollandaise sauce as you would add it in by spoon one at a time whisking it in to your new warm hollandaise and it will be just as good as the first day. it will not separate and will hold well for service.

Properly made hollandaise sauce can be refrigerated fir 2 days , best way is warm up a portion in a glass ball over hot water , add a touch water and whisk gently until warm ...perfect good as new

This might sound a bit unorthodox but, you should be able to keep the sauce for at least a day (or maybe more) in a water bath (sous vide / fully submerged) between 54C and 60C. My goto temperature for pasteurizing eggs is 57.5C, but in your case I would go for 55C.

Oh, yes, you can. There is a way, when you fold in beaten egg whites (soft peaks) after you made your hollondase, not only would those bulk out the sauce and make it able to be kept on warm for long without curdling, but also that would make it able to keep the sauce in the fridge for several days (so that you could have it reheated later) and would even make it to have it frozen for much longer storage, if really needed.