I'm really happy I pushed the 500 unique pets barrier recently, and I'm also very happy I've been able to raid Tier 1-14 in the patch they belong too. :D
I've been most excited about all the little dumb achievements normal people don't care about :P
My favorite achievement so far is still my undying title, mostly because while it was after Ulduar came out it was before Trial of the Crusader came out.
I was most excited to get my 2 legendary weapons from farming Molten Core for blood of the mountain. I can't use the sword but it was still nice to achieve.
Hand of A'dal
Probably my Reigns of the Raven Lord
Winning Ashes of Al'ar) I have 78 runs for it))) I got drunk that day transfer :D
When i get my Reins of Poseidus!Or when i fish my rat in dalaran :D
Winning the Darkmoon Eye the first week it was available!
For me it was completing my 2nd legendary weapon on my Shaman. I completed Thunderfury, Blessed Blade of the Windseeker when i got both halves of the bindings to drop while farming for the Eye of Sulfurus on Ragnoros. It was an awesome day when the Eye finally dropped, I literally threw my hands in the air like I just wont the jackpot!
Reins of the Black War Bearwas one of the best nights i've had on wow
Finally after all these years getting my Tier 2 set complete for some sweet looking Transmog'ing. Damn those shoulders seemed to take forever to drop (well only 7 yrs really.)
Being the first lvl 90 panda monk in my guild
A Sha-Touched weapon, now to work on the crystal
My Raven Lord mount, it's blue and yellow, and pretty, it can't fly, but i like it anyway :)
Achieving Loremaster was the hardest and most rewarding thing I've ever done in the game. It took an impossible amount of time trying to find every quest and ignoring raids while I was on a MISSION =) When the achievement popped I could have cried. Getting the letter, I was SO proud and wore my tabard SO proudly. Wowhead was SERIOUSLY instrumental in helping me. Getting What a Long Strange Trip It's Been was 3 years in the making thanks to School of Hard Knocks. The night I finally got it, I explained to my non-gamer boyfriend that he was going to hear me scream things on Vent he didn't normally hear me say. I FINALLY capped a flag in Eye of the Storm after being death gripped and stunned all the way, and screamed in excitement... no achievement. A guildie on Vent went, "Where's your orphan?" It had despawned. I could have DIED. =P
Probably the ultramarine battle tank from archeology. Took me around 500 tol'vir solves to get it which is alot higher than the avrage so I didn't think I would ever get it : /
The best title to me is "The Insane", because I have been called insane countless times in real life and over vent, so getting this achievement is very important to me. Wish me luck on grinding lockboxes!