Quality of Life Addons

I don't run with a lot of addons.  I use the default interface for most things, including raid frames and healing.  I have the standard minimum for raiding - a boss mod (DBM), a threat meter just in case, and a DPS meter (Recount) to make sure I'm not entirely useless.  Most of what I use is for minor quality of life, things, though.  Here are the ones I absolutely can't do without:

• Altoholic:  Keeps track of what I've got on who, when the last time I logged everyone on was (I do a full log-on of my random little alts about every three weeks), who has auctions I should check on, and so forth.  It also keeps track of what my toons are wearing, so when I log over to a crafter, I can easily see who needs upgrades in which slots, or which slots aren't enchanted.

• AuctionLite and AuctionLite Improved Search:  I love love love the purchasing interface for AuctionLite, and I appreciate the searching/pricing options on the selling tab.  The improved search purchasing interface lets me search specifically for Battle Pets, and all the various entries for each pet are smooshed into a single entry in the big list, so I can easily see if any of the handful of auctionable pets I don't have are listed.

• BattlePetCount:  There are other similar addons out there; this is the one I use for the mouseover information and quality flagging (it tells me if what I'm fighting is better than what I've got with an asterisk).  Given that I occasionally try to up my standing on my realm on WarcraftPets, it's been fairly handy.
• CT:  I'm using three parts of CT: MailMod, MapMod, and PartyBuffs.  MailMod is nice for opening a lot of mail at once and having a log of just who you just mailed that 500g to, and it's the one that makes me realize a patch has disabled my addons (because they're now "out of date"), because it's the first one I notice missing.

I run others, but these are the ones that I miss the most if they're broken or if I haven't yet re-enabled addons.