I have, and it just did work when I needed it to or did work properly. For example the distance and power of the n900 ir is fairly weak. For example with my old newton 2100 I could change the station of store tvs from the street when walking by!! The n900 not even in the same room often. The sharp zuarus 550 had this same issue.

Not saying it not useful, just saying it did end up being that useful on the n900 for me.

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