Zos Chanukah is the last chance to grab a bit of chiyus from Chanukah -- “Zos asu v’chyu,” Yosef tells his brothers -- before it fades away into the distance.
The Sefas Emes explains that the mitzvah of menorah is “l’haniacho al pesach beiso,” to leave it by the doorway –- the chag moves on, but the menorah needs to be left behind and stick with us. The gemara (Shabbos 23b) speaks about “ha’zahir b’mezuzah… ha’zahir b’tzitzis… ha’zahir b’kiddush…,” but uses the term “ha’ragil” – not ha’zahir – “b’ner Chanukah” (see Maharasha). How can you be “ragil” in doing something that lasts for only just over one week? By taking the spirit of Chanukah with you and making it part of every day.
When Ya’akov meets Eisav he tells him to go on ahead to Seir, as he, Ya’akov, must travel slowly “l’regel ha’melacha u’l’regel hayeladim.” Rashi writes that we will only get to Seir with the coming of Moshiach and ultimate judgment for Eisav. We have to wait for the tikun of Jewish history that started figuratively at the head of galus to make its way down to the bottom of the feet, to the "regel." (Perhaps this is what Yosef meant when he told his brothers, “Meraglim atem.” ) "Haragil b’ner chanulah" -- the Radomsker explains that ner Chanukah is our tool to get to the regel, that ultimate tikun. We are right there at ikvisa d’meshicha, the “heel,” and just need to push a little harder.