http://traduku.net/abctajpu/ abcTajpu. type in any language♥
http://adblockplus.org/en/ Adblock Plus
https://firefox.maltekraus.de/extensions/add-to-search-bar Add to search bar - use any search form directly from your search engine list (and see Second search below)
http://code.google.com/p/firefoxcalculator/ just a calculator. i hate leaving the browser or even my tab just to count something.
http://check4change.mozdev.org/ Check4Change refreshes for you automatically and checks whether the selected text is still exactly the same. it's been with me through many worries.
https://addons.mozilla.org/en-US/firefox/addon/copy-as-html-link/ Copy as HTML link. the Finnish keyboards have one or two key more and as a result i can't type < and > (typed using abcTajpu - you can also set shortcuts for your most used symbols/text) directly. i've meant to make my custom keyboard layout for like forever but for links it's much easier to just right-click;)
https://addons.mozilla.org/en-US/firefox/addon/custom-download-manager/ Custom Download Manager. i always hated how the downloads were in a new window :D
http://smarterfox.com/news/ FastestFox it does many things but i love it most for making pages with "next" on them endless - it just loads the new one as a continuation of the one you're browsing. unfortunately it doesn't always deals with < and other symbols well and works backwards on myp2p.
http://realityripple.com/software/xpi/fe/ Fierr. refreshes the page for you every 10 seconds if it's not available. great during lj fails. i sometimes feel sorry for it and its hard work.
https://addons.mozilla.org/en-US/firefox/addon/fuzzy-time/ Fuzzy Time. I bloody love this clock. (used Copy as html link for the link;)) But it's bloody expensive and i look at my browser far more than i'd look at a clock. so, for about a year i haven't had a proper clock in the corner of my screen, forcing me to use this one all the time.
http://www.greasespot.net/ Greasemonkey. 39534969563 more things like add-ons - scripts. i mainly use those that let me laugh at the people who get fucking paid accounts for the same functions. (expanding threads and subscribing to specific comments)
http://coralietab.mozdev.org/ IE Tab Plus. let's face it, sometimes we do need IE. it lets you just open it in a tab. somehow it even opens just a couple of seconds slower than a regular new tab.
http://lazarus.interclue.com/ Lazarus. it's currently saving every letter i type here in case lj fails. i won't lose this post and i don't need to copy obsessively to ensure this. i don't even need to tell it about lj's problems - it just saves everything.
http://lightshot.skillbrains.com/ Lightshot. 357945793459x more control than the PrntScrn button. allows you to quickly upload it too.
http://yellow5.us/firefox/linkification/ Linkification. makes links clickable.
https://addons.mozilla.org/en-US/firefox/addon/livejournal-hook/ Livejournal Hook. select text and tag it as a cut or lj user. and 57937579x more lovely things that i don't use :D
http://en.design-noir.de/mozilla/locationbar2/ Locationbar2. allows you to trim the url easily to "go a level up".
http://menueditor.mozdev.org/ MenuEditor. See the number of add-ons? almost each of them creates its menu options somewhere. i don't need them ALL and especially not all of the default ones. if this post inspires you do get many add-ons, be sure to get this one to clean up your browser :D
http://yellow5.us/firefox/osb/ Organize Statusbar. does the same with your statusbar. every add-on considers itself important enough to be in your statusbar. and to decide its position. nothx.
http://piro.sakura.ne.jp/xul/_multipletab.html.en Multiple Tabs Handler. select multiple tabs to close them all. or to close the non-selected ones. or duplicate tabs. or do many other things i don't even need :D
http://readitlaterlist.com/ Read It Later. who's not guilty of bookmarking stuff you just need to read once? i'm not anymore :D
http://www.reminderfox.org/ ReminderFox. got it during the attacks on lj so that my fandom life didn't depend on which tabs i have open. i'm really not organized enough to download special software just to be more organized.
http://netticat.ath.cx/extensions.html Righttoclick. gives you your right back.
http://piro.sakura.ne.jp/xul/_secondsearch.html.en second search. no need to limit yourself to just one default engine - or to change your default one all the time when you really just need to use a different one NOW.
http://www.youtube-mp3.org/ youtube to mp3. enough said, i'm kinda tired :D
and these are not even all i use or especially all i have installed :D
if there was an add-on to get me more icon spaces, i'd use this one:
feel free to use, no need to credit. as you can see i fucking love firefox.