I've always loved "Be Still, My Soul." In a sort of ironic twist, I think one of the manliest things we can do is to turn control of our lives over to the Lord and trust Him. I would argue it takes more self-control than just about anything else I've tried. I admit I'm still struggling to balance that I need to do with what I need to turn over to Christ, but that may be a whole 'nother discussion.
"I Believe in Christ" has always done it for me. Especially at a conference when all the guys hit the bass notes really hard. That tone mixed with the lyrics gives me chills every time. Excellent question.
Oh say, what is truth? 'Tis the fairest gem
That the riches of worlds can produce,
And priceless the value of truth will be when
The proud monarch's costliest diadem
Is counted but dross and refuse.
Yes, say, what is truth? 'Tis the brightest prize
To which mortals or Gods can aspire;
Go search in the depths where it glittering lies
Or ascend in pursuit to the loftiest skies.
'Tis an aim for the noblest desire.
The sceptre may fall from the despot's grasp
When with winds of stern justice he copes,
But the pillar of truth will endure to the last,
And its firm-rooted bulwarks outstand the rude blast,
And the wreck of the fell tyrant's hopes.
Then say, what is truth? 'Tis the last and the first,
For the limits of time it steps o'er.
Though the heavens depart and the earth's fountains burst,
Truth, the sum of existence, will weather the worst,
Eternal, unchanged, evermore.
I personally love to sing the Battle Hymn of the Republic. And ever since Camp Helaman I have loved Called to Serve, Every time it takes me back to the sound of 280 16-20 year-old boys and men singing it loud and proud. Come to think of it any hymn that takes me back to that is now a favorite.
My favorite Man Anthums are Brightly Beams our Father's Mercy #335. I love the line "but to us he gives the keeping of the lights along the shore." When a sailor was looking for a safe harbor he would look for the lighthouse and then line up his bow with the lighthouse and the light the light house keeper held on the shore to guide him safely in. It gives me greater meaning to Matt 5:48 Let your light so shine...
I also love "We Thank Thee O God for a Prophet" #19.
I'd have to agree with most of those listed already, especially In Humility Our Savior, one of my favorites. I heard a stirring a capella version of Brightly Beams our Father's Mercy (male quartet) that still resonates. But I would say my absolute favorite would be "O My Father".
Although I love "Called to Serve", I've never felt it sung quite as strongly as when sung by the missionaries in the MTC. I also like "How Firm a Foundation" and "True to the Faith". However, my favorite is "Abide with Me". And, of course, you can't have a discussion about hymns without someone mentioning "Hie to Kolob".