Verse 138 of Havamal is cited as lore regarding Odin discovering the runes. It states he grabbed the runes. However I do not think this refers to Odin discovering the runes, Odin grabbing the runes likely refers to him preparing to speak, it is likely a poetic way of saying he was getting ready to either speak or write. All language is composed of runes/letters.
Odin's Quest after the Runes
I trow I hung on that windy Tree
nine whole days and nights,
stabbed with a spear, offered to Odin,
myself to mine own self given,
high on that Tree of which none hath heard
from what roots it rises to heaven.
None refreshed me ever with food or drink,
I peered right down in the deep;
crying aloud I lifted the Runes
then back I fell from thence.
Nine mighty songs I learned from the great
son of Bale-thorn, Bestla's sire;
I drank a measure of the wondrous Mead,
with the Soulstirrer's drops I was showered.
Dost know how to write, dost know how to read,
dost know how to paint, dost know how to prove,
dost know how to ask, dost know how to offer,
dost know how to send, dost know how to spend?
The Song of Spells
Those songs I know, which nor sons of men
nor queen in a king's court knows;
the first is Help which will bring thee help
in all woes and in sorrow and strife.
http://www.pitt.edu/~dash/havamal.html#runes
It is not the runes which he discovered on Yggdrasil, it is more likely it is songs which he discovered. Mantras and incantations which are alluded to in his song of spells. Affirmations. According to our understanding of history runes share a common root with the latin alphabet, both of which can be traced to the Etruscan old italic alphabet.
An magical thing about the runes is likely related to morphic resonance attached to it due to its historical use for inscribing written incantations upon things, something the latin alphabet was used for as well but to a lesser degree.
Odin grabbing the runes was likely a use of poetic language used to precede his construction of the songs/mantras used as spells. Poetry was a craft used to construct spells prior to being used to express emotions. Things such as rhyming and alliteration were used to accentuate ones affirmations.
A spell is to use language in a manner so that the words have a relationship with time that is the opposite of a communication. A spell uses language creatively whereas non-magical language uses language to reflect the world or to communicate regarding what the world is.
So for example if your town is bad and you wish it to be good a magical use of language would be to say "my town is good". Even though you would be lying you would be speaking using the creative power of words. AN example of a common evil spell is when there is a smart person who people call stupid or crazy, they are not actually crazy or stupid but the words are used as forms of psychological aggression to wound their mind.
Magic is to speak about what one wishes to be as if it was.
A parapsychological blessing upon someone is to speak good affirmations for them from a distance. There are three dimensions of space, time is the fourth, and mind is the fifth. All spacetime is contained within all points of mind. For this reason one can speak regarding someone even at a distance, saying this person is healthy(regardless of whether or not it is true in the present time) as a form of blessing. One can also focus the blessings silently in the form of mental suggestions... thinking positive suggestions towards them. Such as "You are healthy" etc.