I've been us­ing Trow­el for a month now and still like it very much, even if I do say so my­self. Trow­el is a Perl script I wrote - based on Richard Stelling's orig­i­nal im­ple­men­ta­tion - that uses the Growl frame­work on OS X to smooth­ly pop up the tweets that ap­pear in a Twit­ter time­line. There's prob­a­bly a ton of ap­pli­ca­tions that of­fer sim­i­lar func­tion­al­i­ty, but this of­fers the full pow­er of the Prac­ti­cal Ex­tract­ing and Re­port­ing Lan­guage - a.k.a. Perl - to quick­ly adapt it to keep the time­line us­able and keep Trow­el from clog­ging up the en­tire screen with tweets.

My con­text is that I use it on an iBook with a 1024x786 screen and I fol­low about 70 peo­ple al­most 24/7, which gives me with an up­date in­ter­val of two min­utes a cou­ple of tweets once in a while. Since click­ing on links in quick­ly van­ish­ing Growls wasn't feasable I opt­ed to just open the links in the tweets au­to­mat­i­cal­ly. This can also be fil­tered be­cause I'm not in­ter­est­ed in every sin­gle pro­gram on Arte, or every foursquare check-in, but I don't mind col­lect­ing a bunch of tabs in my brows­er with fun­ny youtubes. Trow­el also no­ti­fies when you lose or gain fol­low­ers, and it keeps a cache of avatars it dis­plays with al­pha-transparan­cy in the Growls, just to keep it as smooth as Growl in­tend­ed.