It was not just an off-hand 'optional' or flippant task though - for those that followed these gods, it was a requirement that (they beleived) had dire consequences for life if they didn't offer sacrifice, or if they didn't do it with appropriate reverence.
The Israelites also had a high reverence for God in their sacrifices, and rightly so. They did fear God - they even had a rope around the high priest's waist as he went into the Most Holy Place on Yom Kippur, in case God was displeased and struck him dead - then they could recover the body without trespassing into that place themselves. We look back on these sacrifices as shadows of what was to come in Christ, and His payment and our justification thereby has removed the terror of God's presence, but the sacrifices were a hugely important part of God's plan.
Israel had a murky history with sacrifices, and we do remember the lessons from Scripture that God desired obedience rather than sacrifice, and sometimes I know I fall into the trap of dismissing the sacrifices as less important than they actually were. Sacrifices were instituted by God. Done correctly, and from an obedient (rather than a hypocritical) life, they are described as a sweet-smelling savour to Him. Holy (set apart for God, for His exclusive use and joy), acceptable to God (because they are done in the right way, with the right attitude) - this is our spiritual worship - our reasonable service. We are not doing this as the pagans did out of fear of testy and unpredictable gods, but because of the mercies of a gracious God and Saviour.
In many ways, traditions regarding church gathering have replaced the traditions of sacrifice. There is a modern culture that likes to just do whatever they please at church, but there are some things from Scripture about how we should meet, and particularly about the Lord's Supper/Communion, which are imoprtant traditions implemented by God himself, and should be held in reverence and conducted in an orderly fashion - God is after all not a God of chaos! It is part of a living sacrifice too, I believe, to be living in obedience to God, and setting aside time daily and weekly (where possible) for Him, in the patterns that He has set.
Similarly about being conformed to the world, there is much we can learn about Israel's history. Many of the Levitical ceremonial rules, (that don't apply to Gentiles, but the nation of Israel in that period where they were under theocratic rule), were made to keep Israel separated and distinct from those about them. We need not follow the letter of those ceremonial rules today, as they were not given to us, but the moral separation still applies, and there are some things culturally that we do not (or should not) engage in, in case we are tempted/compromised by our association with ungodly people/activities, and thus mar the testimony and glory we give to God. It is not total separation (pulling apart and refusing any contact, as with some cults), but a separation that protects us, and shows us as different because of what we believe and Who we follow. It is a separation that began when we accepted Christ, and were re-born, we gained new life and were released from the power that sin had over us - our minds were no longer corrupted, they were transformed. Having begun this good work and transformation through Christ, we must remain in/with Him, reading His Word, that our minds continue to be transformed and that we may discern right from wrong, and know His Will. From salvation we have been given an instinct, a re-awakening of our conscience, but that concience can be dulled again if we are not separated from the world and separated to God. We live in the world, but we are no longer of it. We come alongside and live that to the weak we become weak, and all thigns to all men (I Cor 9:22), but showing mercy with fear, hating even the garment stained by the flesh (Jude 23 - just finished a Bible study on this in church).
Looking to examples of living sacrifice, we have the example of that 'Kiwi' clip in the blog (Day 4, Week 5), where the bird was willing to commit suicide in order to experience flying. Similarly, we have a purpose high enough to not care about death at the end, but our purpose is so much greater. Many missionaries have given their lives for the Gospel, but their strength was not so much in that moment of courage necessary to stand strong in the face of death, but the courage to live for God no matter the consequences or hardships.
Recently I finished reading the 6 Lord of the Rings books (no, it's not strictly a trilogy, it is 6 books in 3 volumes ;) ). And having this passage in mind recently while reading it, the struggle of Frodo and the others as examples of living sacrifice were strong analogies in my mind. Throughout the story there are many points particularly at the start where the hobbits particularly wanted to give up and go home - it would be easier, someone else could do the task - why should they not go back to the comfort of home? Nearer the end, there was the temptation to just lay down and do nothing, or just give up. Their living sacrifice was their willingness to go on, no matter how desperate the circumstances, no matter how tired they were. Even at the end, where they had no hope of returning alive - they only had enough food to get to the mountain to destroy the ring, but none to get out again, they resolved to press on. To die for Christ takes a moment's courage, to live for Christ takes His eternal strength, for we depend on Him.
Now to Him Who is able to keep you from stumbling, and to present you blameless before the presence of His glory with great joy, to the only God our Saviour, through Jesus Christ our Lord, be glory, majesty, dominion, and authority, before all time and now and forever. Amen. (Borrowing a prayer from Jude 24-25)