Someone has been paying attention! I've mentioned using a few interesting potions on a few people's character builds but nobody has ever posted a build using them sadly (I will be soon). Alchemy truly is the best skill in Skyrim, but I may be slightly biased

Samjt's Crusader uses it  It was one of the reasons my first build was cancelled...

Build it, and they will come.

BUILD IT ALREADY!

Never make a build for the sake of posting it... 

What is this uber potion I hear of?

Any links to where it is featured?

Here it is, Sangreal 

@Sangreal » It's a custom Fortify Magicka potion that uses Salmon Roe as one of the ingredients. There's a bug with Salmon Roe that makes it rather unique: Presumably the Fortify Magicka magnitude and duration base values were switched, so it provides about 12x as much magnitude as any other custom Fortify Magicka Potion, but it only lasts for 5 seconds. Just long enough to cast a Master level spell such as Dragonhide.

Ahha!

I remember now vaguely seeing this. Seems quite a hassle for a Dragonhide cast. Well maybe for bosses, but I myself was always too lazy to cast it on my mage, even before tough battles. Thus getting whooped.

Didn't see this so I'm replying late.

As posted, you can see how strong the potion is.  With 100 skill and all relevant perks (with no fortify alchemy gear) the 'Fortify Magicka' effect maxes out at +750 magicka for 10 seconds; with Alchemy gear my potions give me over +1500 Magicka which allows me to use any spell in the game without investing a single level into Magicka. It only lasts for 10 seconds but that is enough time to reliably cast two master spells before it runs out.

Dragonhide breaks down as follows:

• 837 Magicka base cost
• 494 Magicka @ 100 skill (-41% cost)
• 247 Magicka with Master perk
• 692 Magicka dual-casted (yes you can!)

I drink a 'Fortify Alteration' potion (base increase is +60% duration, 123% with the Fortify gear I use) then I drink the fortify magicka potion before Dual-casting Dragonhide.  Dual-casted with Stability perk and potion my Dragonhide lasts for ~220 seconds (almost 4 minutes).  I only use this combo for tough fights that I know Ebonyflesh won't cut it for. 

Honestly James, Enhanced Crossbows won't hurt MFD too badly. You won't be as OP but it's still viable. If anything, it's a good way to nerf yourself.