Something that many Esperantists have to contend with is the perception that a planned language is somehow useless, something on a par of Pig Latin. (One of these is a co-worker and friend of mine, who often reminds me of this opinion.)
But consider this… On Friday, I IM-ed a complete stranger in a foreign country and we chatted for an hour completely in Esperanto… After introducing ourselves, we discussed our respective blogs, programming languages such as PHP and C#, languages in general, mystical perspectives in Buddhism and Christianity, personal experiences and viewpoints, etc.
What’s remarkable about this, is I’ve only studied Esperanto seriously for about five-and-a-half months. If I had to guess, I’d say I’ve spent at most 120 hours actually concentrating on the language, and probably less than that. Although I made many minor mistakes, I was well-understood by my fellow speaker (whom I now consider a friend). This was confident and easy communication that enabled me to say whatever I wanted to. Esperanto enables me to have the ability to communicate easily with any of the hundreds of thousands throughout the world who have taken the time to learn it, whether they’re Dutch, Spanish, Brazilian, Chinese, Japanese or Iranian… And that investment is miniscule compared to what’s required even with relatively "easy" Indo-European languages like Spanish.
Last year, I studied Spanish for twice as long as I’ve studied Esperanto, and I was nowhere near having the ability to converse easily about anything… I’ll return to studying Catalan and Spanish soon, and I expect the experience of attaining proficiency in Esperanto will help greatly in learning those languages more quickly and easily. (Numerous studies have shown that to be the effect.) My suspicion is that it will go like this:
T(Esperanto + other language) < T(learning other language alone)