Seriously, don't... While it may have had its merits in the days of extremely flexy rims for the majority of modern components it really will not give you any noticeable gains. With that being said, I still will occasionally get bored and tie and solder some personal wheels.
So I was talking with Nancy from Family on Bikes, the family who among other big adventures has toured from Alaska to Argentina, about why do touring cyclists let themselves get into very unsafe situations simply from letting maintenance issues go for far too long. The most recent I read in a touring journal was yet another person stranded because their brake pads have worn through their rims (remember, with rim brakes rims are a wear item) to the point the sidewall split. Failure like this takes so long to happen that it honestly blows my mind it happens so frequent so we were trying to figure it out. She asked me to write an article for her blog about how to catch small problems before they grow into much larger ones and this is what I came up with.
For what it is worth, you should spend some time on their site if you are a fan of touring, Nancy has also wrote a few great books about bike touring, some of them family oriented, some were before they had kids. My personal favorite is, "What Were We Thinking" and is worth the read.
Here is a link to the article I wrote.
Bicycle Maintenance While on Tour
Obsession, or passion? Who am I to judge? Either way I simply love building wheels for those who appreciate quality!