When I posted the other day about tasty iced peppermint tea, I forgot about my other new favorite summertime drink: limeade. I could drink this stuff all day. I make mine with all the limes and/or lemons in my fruit bowl that look like they might go weird soon (I try for at least six or seven of them -- enough to get between 3/4 and 1 cup of juice). Juice them into a pitcher. Add sugar to taste -- I am a sourpuss so I do about 1/3 cup of sugar to 1 cup of juice, but you could easily double that if you like the sweets. Stir the sugar and juice together like crazy until the sugar dissolves. Then fill up your pitcher with water (about a quart or so, I'd say). Stir it up some more. Taste it. Add more sugar if needed. Serve over ice.
And since all my favorite summertime drinks must be able to convert into cocktails at a moment's notice, don't forget that you can put vodka in this too!