[Robadob]

Interesting concept, shame it's limited to the US (understandable due to dubious legality of shipping unclassified chemicals between jurisdictions).

Been interested by the apparent 'attention enhancing' qualities of L-Theanine, although not gone as far as purchasing any. By coincidence someone got me into drinking green tea a couple of weeks ago, I haven't noticed any visible change. Although I expect my problem is concentrating on the right thing, rather than simply failing to concentrate.

[arsenico]

From my personal experience, L-Theanine, coupled with caffeine, produces very serious results in terms of negating bad coffee effects, increased focus and productivity, and better sleep

[Legogris]

Same here. A couple of pots of strong sencha (Japanese green tea) give me a huge boost in energy and mood, without the negative effects of derealization, tunnel vision and restlessness I get from too much coffee.