I have some that really drive me nuts:
1) It's "taken aback" NOT 'taken back' (omg, BUGS!)
2) Say 'regardless' not 'irregardless'
3) And lastly, you don't need to say 'With that being said'; you can just say 'That said'
The their/they're, to/too and your/you're stuff can bug me, but sometimes those mistakes are just due to typing too fast or whatnot - rather than being due to not knowing their proper use.
With that being said, I'm still
taken back by how many little mistakes are made -
irregardless of spell check
.